Medication for killing pain
Must have its focus on the brain.
What else it affects, who knows?
A hint comes from a bloody nose.
I did finally take a shower
Getting the benefits of clean power.
Afterward you start anew
Though now there's not much to do.
My right arm held immobile
What little thinking ignoble
I am slowly coming to understand
Total reliance on the right hand.
I should be thankful for the left,
Far from totally bereft,
Without it I'd be a wretch
With nothing left but to kvetch.
Monday, September 24, 2012
Tuesday, September 18, 2012
Putting Paris in a Bottle with IFs
I was trained in grad school as a math guy. Truth could be found by working intensively through a model till all its implications were well understood. It was called economic theory and I was a practitioner of the art. I carried that over to when I became a faculty member. My second semester at Illinois, spring 1981, my teaching load consisted of the graduate math econ course, where I did a reasonable imitation of Stan Reiter pushing the class through its paces while reading Debreu's Theory of Value, and the undergraduate math econ course where I lectured more and worked through David Gale's The Theory of Linear Economic Models. One of the students in that undergraduate course worked as an assistant for a colleague of mine. She was a double major in econ and math. I thereby indirectly learned that my class was more mathematical than the courses she took from the math department. This reflected my training and then orientation. "The real world is a special case," was an expression we used with some regularity, reflecting that we prized generality in the results. I loved and still love both of those books, on a purely intellectual plane.
To make the ideas in these books one's own there are certain things one must do. Some of this is common to making any ideas one's own. One thing, in particular, is unique to doing math. First and foremost you must play with the elements of the model - get a sense of what they are about and familiarity with them, learn little tricks about them that might prove useful later, perhaps find multiple paths to the same conclusion. Developing this sort redundancy is a very good thing. To know something you have to know it in many different ways. Then you have to do proofs. Proofs entail a kind of creativity in coming up with an argument that works. It's not the same creativity as when coming up with fundamentally new results. A student reading one of these books knows that there were others who have come before them and who discovered the results and proved them. But the student isn't sure whether he is replicating the argument previously found or finding a new argument that nonetheless leads to the same conclusion, since the arguments made by the authors are not completely spelled out. There are end of chapter problems that are enlightening to solve. Some of those are proofs. Neither book comes with an answer key.
The third thing is to apply the results in a specific context, really many specific contexts. This is called transfer. To learning theory folks, transfer is the be all and end all demonstration that learning has occurred, to the learner and to any outsider who might attempt to measure the learning. Perhaps play is necessary at the beginning as a means of acquisition. But transfer is just as necessary to show that the play did not go for naught. This gives a two-prong view of learning. Debreu in writing Theory of Value makes the prongs explicit. The first chapter is on mathematics where the fundamental tools and results (convexity, upper semi-continuity of a correspondence, asymptotic cones, fixed point theorems) are obtained. The rest of the book is applications, using the tools already developed in the context of the General Equilibrium model. But Debreu believes in doing the proofs. So his really is a three-prong approach.
Ironically, early Sunday afternoon the family went out for brunch to celebrate my wife's birthday. My younger son is a freshman in Engineering and he said he liked his calculus teacher who makes fun of the engineering students because they want to learn the math without doing the proofs. The older son, a junior also in engineering, verified this proposition. I suppose it balances out because I want to be able to drive a car and I certainly don't care how it works under the hood. But I am a bit befuddled that the older one, in particular, seemed so accepting of this view. How can he be my son and not care about the proofs? Are these attitudes only due to acculturation?
Let me return to the economic theory. In both of these books convexity plays a crucial role, particularly in the form of the supporting hyperplane theorem, Farkas' Lemma in Gale and Minkowski's Theorem in Debreu. In two dimensions this says that through any boundary point of a convex set you can find a tangent line through the point such that the entire set lies on or on one side of the tangent line. The economic interpretation is as follows. If that boundary point is an optimal allocation, then since the tangent line is described by the point and the normal to the line, and that normal vector can be interpreted as a price system at which that allocation maximizes profit in the set or minimizes expenditure in the set, it follows that valuation is the dual of allocation. There is immense beauty in this result and much intuition ensues by applying it extensively.
The world of Adam Smith in the Wealth of Nations is convex. It is a primarily an agrarian world of small farmers and manufactures, shop keepers and small merchants, none big enough to influence the course of events in and of themselves. Only in aggregate does their power manifest. For the mathematics, it is a delightful world in which to reside.
Convexity is not the world of QWERTY. Nor is it the world of the Academic Calendar, where the summer term is of different length than the fall and spring terms. And it isn't the world of social networking and Facebook. Indeed the first two examples in this paragraph are exemplars of Darwinian competition. A certain solution to a particular problem takes hold. Other solutions might very well have been available at that time. Serendipity selects the one we now know about. Then a bunch of related economic activity emerges around those solutions and those solutions become locked in, essentially impossible to alter. The third example is meant to show that what we have now is a kind of Darwinian competition on steroids. The players understand lock in very well and after they have found their toehold many of their actions are made with the intent to accelerate and intensify the lock in.
Given that, I have wondered how these math/economic models have influenced our views of politics. It is well understood that the Adam Smith economic world provides the background setting for Jeffersonian Democracy, the coincidence that Wealth of Nations was published the same year as the Declaration of Independence buttressing this view. Prominent in the Jeffersonian conception is that Government must be severely limited, because it might be the agent of tyranny. It's a point well taken. But in a world where big corporations facilitate customer lock in, might there be tyranny by those corporations as well? This possibility seems exempt from consideration, at least by those libertarians who are so worried about government tyranny. Here the exemplar of the tyrannical corporate titan is probably not Mark Zuckerberg but rather Bill Gates. Yet he remains more of a folk hero than anything else. Might that exemption be because people haven't learned the economics of Darwin but only the economics of Adam Smith?
Much of what we do teach today at the undergraduate level is derived not directly from Smith but rather from Alfred Marshall, the father of marginal analysis. Marshall developed a mathematical approach that is (barely) tractable by the novice in the subject. Because it is intuitive for those who practice the art, marginal analysis dominates the way most people think about economics. Yet marginal analysis is steeped in convexity and hence it limits the possible worlds we might consider. To my knowledge, there is no tractable math version of Darwinian competition suitable for teaching at the undergraduate level. And producing one is no easy task. Marshall's model is static and that greatly aids in making the math tractable. A Darwinian approach is essentially dynamic and stochastic. This makes things very difficult to explain to the non-math person. As Daniel Kahneman convincingly argues in Thinking Fast and Slow, we humans are not hard wired to think about randomness. We impute causality everywhere. A math model that has randomness at its core will be non-intuitive.
What is a conscientious economics instructor to do? One possible approach is to do math modeling for the straightforward stuff and take a discursive but story telling only approach to anything that is more complex. Indeed, I tried that the last time I taught intermediate microeconomics, spending much time on marginal analysis but also covering Paul David's paper on QWERTY. Yet I've found there is a kind of tyranny of the math modeling. Questions about the math models are much easier to place on exams since these questions are "objective" and much more readily graded. Further there is a tradition of economics courses emphasizing the models, so that if one goes over to the narrative approach too far, then even if that makes sense in the context of the course it is apt to be confusing to the students in the context of the tapestry of other courses with some economics that student will take. For intermediate microeconomics and principles of economics too, which serve as prerequisites for subsequent economics courses, there is further an expectation by those downstream instructors that the students will have been drilled in marginal analysis. The upshot is that students treat the Paul David paper as a curiosity only and don't make the connection that the underlying economics in it explains much current economic activity.
Let me turn to a related issue. I taught an upper level undergraduate special topics course last spring on the Economics of Organizations and I'm teaching the same course now. In the spring version my enrollments were very low so I opted to teach the class as a seminar. I decided for the math that I would present some of it, but in order for the students to get their fingers dirty I would have them present on some of the fundamental papers in the area, doing the presentations in teams of three students. I would coach the teams outside of class on the presentations, discuss the ideas in the paper, help them get oriented. This approach proved an unmitigated disaster. Part of it was some team members missing those outside of class meetings. But the bigger part is that the students had no conception about how to present the mathematics. They showed no play with the content and no transfer of the math to related ideas in the paper. With respect to the equations, one team did the equivalent of text to voice software They simply read aloud what was printed in the article. In my view they provided zero value add to the other students in the class.
It has always been a struggle with the student's math ability in microeconomics courses. They've had the prerequisites but that matters not. The bulk of the non-engineering students have never learned how to take the ideas in a math model and make them their own. Many have trouble reading the graphs that are common in microeconomics classes. Because the activity is unpleasant for them, most don't persist with it enough to get familiar with the content.
In the late 1990s I came up with a mechanism that addressed this issue. Students did the written problems, from the end of the chapter in the textbook, in teams. They'd submit each problem online individually and usually in the first go round they allocated the problems by some division of labor among the team members. If they didn't get maximal credit on that initial submission, my mechanism allowed that some other member of the team could resubmit the problem for additional credit. And that cycle could repeat, until the deadline for the homework. The idea behind the mechanism was to encourage discussion among the team members about how to work the problems. Further, and more importantly, I had online TAs, students who had taken the class previously and done well in the class, available to answer questions from the students about how to improve their answers. The TAs had my written up solutions to the problems and they were instructed not to give the students the answers but rather to help them think it through. While the mechanism was far from perfect and we had some bumps along the way, it actually was quite effective. Many students made use of the online office hours and came to rely on their interactions with the TAs to learn the economics. Were I teaching a high enrollment class (that class had 180 students) I'd adopt something similar, even now.
But my class is one tenth that size and it is only me, no TA, not even a grader. So I needed to do something different. The philosophy behind my approach this semester is articulated in an early post to my students. We will do models, and the math with them, but we will critique the models for the tension between the modeling assumptions and reality or for the tension between the assumptions of one model and another. For working through the models themselves my solution has been to produce interactive Excel exercises, dialogic learning objects if you will but of a special type. The next part of this essay will discuss those in some length.
Before getting to that, let me explain my admittedly obscure title. When I was an assistant professor, I was very fortunate that one of my fellow assistant professors in the Econ department, also a theorist, was the daughter of the Belgian Ambassador to the U.S. We became good friends. She taught me many things outside of economics - what very well prepared food was like, how to consider political/social issues from a more global and less provincial perspective, and lots of clever little sayings. One of those was, With if's you can put Paris in a bottle, an admonition to beware of the conditional in one's thinking because anything might follow thereafter. In my use of Excel I make massive use of the conditional - the built in IF function is all over the place and conditional formatting is used as well when giving automated feedback to a student response to a question. I don't know that I've really put Paris in a bottle with these workbooks, but some of it is quite nifty in my view. So the title is a bit of over promotion of the work and at the same time offers a long overdue note of thanks to my friend.
* * * * *
At this point I've made 3 of these homeworks. The first is a tutorial for the student to learn how they work - what the student must do, what type of feedback the student will get after inputting an answer, how they get credit for the assignment. It doesn't have the interactive graphs that are a feature of the real homeworks, but in other respects the structure is the same. I encourage you to try it. To do so you must download the file You need a current version of Excel but your knowledge of Excel can be minimal. Put in some string for in the NetID cell. Choose an alias. It doesn't matter which here. Know that the students are assigned aliases and they must choose the assigned alias to get credit. But you are doing it without caring about the credit so it doesn't matter. It should only take 5 minutes or so to complete. You have to get all the answers Correct to be able to submit it. There is no partial credit. There is a participation credit when a student gets it all right and then submits the key via the Web form.
The second is a review of efficiency concepts that students should learn in intermediate microeconomics. (It turned out that many students hadn't previously seen the Edgeworth Box, the topic of the second worksheet.) It has the interactive graphs so you might try this one too, at least answer a few questions correctly and see how the graph updates when you do. This is achieved by having the series that generate the graph to be conditional on whether the student has answered the appropriate question correctly. For example, this is the entry in the cell that gives the series name for the series called Demand Curve.
Let's deconstruct this one entry. We'll leave it to the reader's imagination to understand how the rest of that series and other series are constructed. In this case the student puts an answer into cell G32. The feedback the student gets is in cell H32. The content of cell H32 has one of three values. It is blank if the student has yet to put an answer in G32. It is Incorrect if the student has put in a wrong answer in cell G32. And it is Correct if the student has put in a correct answer in cell G32. The quotes you see denote a text string between the left quote and the right quote. Absent the quotes Excel interprets entries numerically. The IF statement above can then be read as: if the student answers the question correctly then title the series Demand Curve, otherwise title the series with a blank string.
The student doesn't see this IF statement. It comes from cell AC34. But that cell is locked, the font in the cell is white so can't be distinguished from the background, and the worksheet is password protected so the student can't access the cell's content. I hope this gives a little sense of how the worksheet is constructed. There are quite a few other graph plotting tricks that are used, so things get labelled in a readable way to relate what the student is answering to what is being plotted in the graph. I won't cover those tricks here. But I will say that others can be taught them so that if this approach is liked, it can be replicated after some instruction on how to do it.
The real key to whether this approach provides effective instruction is not the cutesy use of technology, however. It is the quality of the authoring. Do the students see the value add to them from doing the homework? One critical idea here is that the homework is not assessing what students should have already learned elsewhere. The learning should be happening while the student answers the questions. In that sense, the aim of the homework is to be like play in getting the student familiar with the issues and to encourage her to spend enough time on the content to get some familiarity with it. The further aim is to convince the student that the models provide insight that wouldn't be apparent from a text only approach. And, of course, I hope student gets some insight into the underlying economics.
It is hard to author this way, no doubt. But one does develop facility with the approach over time. So the bigger issue with the writing is coming up with what one wants to do conceptually and then how to illustrate the concepts. The actual placing entries into the cells then goes reasonably quickly after that.
I am optimistic about the approach and the early feedback I've gotten from the students indicates they like this too. We'll see if I can keep it up and sustain their interest in the course this way.
The third workbook is about coordination problems and coordination mechanisms. It's a live homework now. You are welcome to try it, but please don't submit your key. It is the first homework with content relevant for our class that they likely haven't seen in other classes.
I believe this approach can work in other courses that have some math in them but that aren't only about the math. Perhaps they could work in math only classes but, but the math instructors I know tend to favor their own tools (not Excel). Way back when I was interested in this sort of thing so the assessment would happen on the local computer rather than on the LMS server and thereby not clog the server near a homework deadline for a big class. That issue is somebody else's problem now. My interest now is the blend of presentation and assessment delivered in homework in a highly interactive way, one that students find compelling. The authoring environments provided to most instructors don't allow for his possibility. But these Paris in a Bottle Excel Exercises are meant to show it is quite possible to deliver very rich content in this way. We should be going after that in what we give our students, especially the implicitly math phobic ones, who won't make good progress with more traditional methods.
To make the ideas in these books one's own there are certain things one must do. Some of this is common to making any ideas one's own. One thing, in particular, is unique to doing math. First and foremost you must play with the elements of the model - get a sense of what they are about and familiarity with them, learn little tricks about them that might prove useful later, perhaps find multiple paths to the same conclusion. Developing this sort redundancy is a very good thing. To know something you have to know it in many different ways. Then you have to do proofs. Proofs entail a kind of creativity in coming up with an argument that works. It's not the same creativity as when coming up with fundamentally new results. A student reading one of these books knows that there were others who have come before them and who discovered the results and proved them. But the student isn't sure whether he is replicating the argument previously found or finding a new argument that nonetheless leads to the same conclusion, since the arguments made by the authors are not completely spelled out. There are end of chapter problems that are enlightening to solve. Some of those are proofs. Neither book comes with an answer key.
The third thing is to apply the results in a specific context, really many specific contexts. This is called transfer. To learning theory folks, transfer is the be all and end all demonstration that learning has occurred, to the learner and to any outsider who might attempt to measure the learning. Perhaps play is necessary at the beginning as a means of acquisition. But transfer is just as necessary to show that the play did not go for naught. This gives a two-prong view of learning. Debreu in writing Theory of Value makes the prongs explicit. The first chapter is on mathematics where the fundamental tools and results (convexity, upper semi-continuity of a correspondence, asymptotic cones, fixed point theorems) are obtained. The rest of the book is applications, using the tools already developed in the context of the General Equilibrium model. But Debreu believes in doing the proofs. So his really is a three-prong approach.
Ironically, early Sunday afternoon the family went out for brunch to celebrate my wife's birthday. My younger son is a freshman in Engineering and he said he liked his calculus teacher who makes fun of the engineering students because they want to learn the math without doing the proofs. The older son, a junior also in engineering, verified this proposition. I suppose it balances out because I want to be able to drive a car and I certainly don't care how it works under the hood. But I am a bit befuddled that the older one, in particular, seemed so accepting of this view. How can he be my son and not care about the proofs? Are these attitudes only due to acculturation?
Let me return to the economic theory. In both of these books convexity plays a crucial role, particularly in the form of the supporting hyperplane theorem, Farkas' Lemma in Gale and Minkowski's Theorem in Debreu. In two dimensions this says that through any boundary point of a convex set you can find a tangent line through the point such that the entire set lies on or on one side of the tangent line. The economic interpretation is as follows. If that boundary point is an optimal allocation, then since the tangent line is described by the point and the normal to the line, and that normal vector can be interpreted as a price system at which that allocation maximizes profit in the set or minimizes expenditure in the set, it follows that valuation is the dual of allocation. There is immense beauty in this result and much intuition ensues by applying it extensively.
The world of Adam Smith in the Wealth of Nations is convex. It is a primarily an agrarian world of small farmers and manufactures, shop keepers and small merchants, none big enough to influence the course of events in and of themselves. Only in aggregate does their power manifest. For the mathematics, it is a delightful world in which to reside.
Convexity is not the world of QWERTY. Nor is it the world of the Academic Calendar, where the summer term is of different length than the fall and spring terms. And it isn't the world of social networking and Facebook. Indeed the first two examples in this paragraph are exemplars of Darwinian competition. A certain solution to a particular problem takes hold. Other solutions might very well have been available at that time. Serendipity selects the one we now know about. Then a bunch of related economic activity emerges around those solutions and those solutions become locked in, essentially impossible to alter. The third example is meant to show that what we have now is a kind of Darwinian competition on steroids. The players understand lock in very well and after they have found their toehold many of their actions are made with the intent to accelerate and intensify the lock in.
Given that, I have wondered how these math/economic models have influenced our views of politics. It is well understood that the Adam Smith economic world provides the background setting for Jeffersonian Democracy, the coincidence that Wealth of Nations was published the same year as the Declaration of Independence buttressing this view. Prominent in the Jeffersonian conception is that Government must be severely limited, because it might be the agent of tyranny. It's a point well taken. But in a world where big corporations facilitate customer lock in, might there be tyranny by those corporations as well? This possibility seems exempt from consideration, at least by those libertarians who are so worried about government tyranny. Here the exemplar of the tyrannical corporate titan is probably not Mark Zuckerberg but rather Bill Gates. Yet he remains more of a folk hero than anything else. Might that exemption be because people haven't learned the economics of Darwin but only the economics of Adam Smith?
Much of what we do teach today at the undergraduate level is derived not directly from Smith but rather from Alfred Marshall, the father of marginal analysis. Marshall developed a mathematical approach that is (barely) tractable by the novice in the subject. Because it is intuitive for those who practice the art, marginal analysis dominates the way most people think about economics. Yet marginal analysis is steeped in convexity and hence it limits the possible worlds we might consider. To my knowledge, there is no tractable math version of Darwinian competition suitable for teaching at the undergraduate level. And producing one is no easy task. Marshall's model is static and that greatly aids in making the math tractable. A Darwinian approach is essentially dynamic and stochastic. This makes things very difficult to explain to the non-math person. As Daniel Kahneman convincingly argues in Thinking Fast and Slow, we humans are not hard wired to think about randomness. We impute causality everywhere. A math model that has randomness at its core will be non-intuitive.
What is a conscientious economics instructor to do? One possible approach is to do math modeling for the straightforward stuff and take a discursive but story telling only approach to anything that is more complex. Indeed, I tried that the last time I taught intermediate microeconomics, spending much time on marginal analysis but also covering Paul David's paper on QWERTY. Yet I've found there is a kind of tyranny of the math modeling. Questions about the math models are much easier to place on exams since these questions are "objective" and much more readily graded. Further there is a tradition of economics courses emphasizing the models, so that if one goes over to the narrative approach too far, then even if that makes sense in the context of the course it is apt to be confusing to the students in the context of the tapestry of other courses with some economics that student will take. For intermediate microeconomics and principles of economics too, which serve as prerequisites for subsequent economics courses, there is further an expectation by those downstream instructors that the students will have been drilled in marginal analysis. The upshot is that students treat the Paul David paper as a curiosity only and don't make the connection that the underlying economics in it explains much current economic activity.
Let me turn to a related issue. I taught an upper level undergraduate special topics course last spring on the Economics of Organizations and I'm teaching the same course now. In the spring version my enrollments were very low so I opted to teach the class as a seminar. I decided for the math that I would present some of it, but in order for the students to get their fingers dirty I would have them present on some of the fundamental papers in the area, doing the presentations in teams of three students. I would coach the teams outside of class on the presentations, discuss the ideas in the paper, help them get oriented. This approach proved an unmitigated disaster. Part of it was some team members missing those outside of class meetings. But the bigger part is that the students had no conception about how to present the mathematics. They showed no play with the content and no transfer of the math to related ideas in the paper. With respect to the equations, one team did the equivalent of text to voice software They simply read aloud what was printed in the article. In my view they provided zero value add to the other students in the class.
It has always been a struggle with the student's math ability in microeconomics courses. They've had the prerequisites but that matters not. The bulk of the non-engineering students have never learned how to take the ideas in a math model and make them their own. Many have trouble reading the graphs that are common in microeconomics classes. Because the activity is unpleasant for them, most don't persist with it enough to get familiar with the content.
In the late 1990s I came up with a mechanism that addressed this issue. Students did the written problems, from the end of the chapter in the textbook, in teams. They'd submit each problem online individually and usually in the first go round they allocated the problems by some division of labor among the team members. If they didn't get maximal credit on that initial submission, my mechanism allowed that some other member of the team could resubmit the problem for additional credit. And that cycle could repeat, until the deadline for the homework. The idea behind the mechanism was to encourage discussion among the team members about how to work the problems. Further, and more importantly, I had online TAs, students who had taken the class previously and done well in the class, available to answer questions from the students about how to improve their answers. The TAs had my written up solutions to the problems and they were instructed not to give the students the answers but rather to help them think it through. While the mechanism was far from perfect and we had some bumps along the way, it actually was quite effective. Many students made use of the online office hours and came to rely on their interactions with the TAs to learn the economics. Were I teaching a high enrollment class (that class had 180 students) I'd adopt something similar, even now.
But my class is one tenth that size and it is only me, no TA, not even a grader. So I needed to do something different. The philosophy behind my approach this semester is articulated in an early post to my students. We will do models, and the math with them, but we will critique the models for the tension between the modeling assumptions and reality or for the tension between the assumptions of one model and another. For working through the models themselves my solution has been to produce interactive Excel exercises, dialogic learning objects if you will but of a special type. The next part of this essay will discuss those in some length.
Before getting to that, let me explain my admittedly obscure title. When I was an assistant professor, I was very fortunate that one of my fellow assistant professors in the Econ department, also a theorist, was the daughter of the Belgian Ambassador to the U.S. We became good friends. She taught me many things outside of economics - what very well prepared food was like, how to consider political/social issues from a more global and less provincial perspective, and lots of clever little sayings. One of those was, With if's you can put Paris in a bottle, an admonition to beware of the conditional in one's thinking because anything might follow thereafter. In my use of Excel I make massive use of the conditional - the built in IF function is all over the place and conditional formatting is used as well when giving automated feedback to a student response to a question. I don't know that I've really put Paris in a bottle with these workbooks, but some of it is quite nifty in my view. So the title is a bit of over promotion of the work and at the same time offers a long overdue note of thanks to my friend.
* * * * *
At this point I've made 3 of these homeworks. The first is a tutorial for the student to learn how they work - what the student must do, what type of feedback the student will get after inputting an answer, how they get credit for the assignment. It doesn't have the interactive graphs that are a feature of the real homeworks, but in other respects the structure is the same. I encourage you to try it. To do so you must download the file You need a current version of Excel but your knowledge of Excel can be minimal. Put in some string for in the NetID cell. Choose an alias. It doesn't matter which here. Know that the students are assigned aliases and they must choose the assigned alias to get credit. But you are doing it without caring about the credit so it doesn't matter. It should only take 5 minutes or so to complete. You have to get all the answers Correct to be able to submit it. There is no partial credit. There is a participation credit when a student gets it all right and then submits the key via the Web form.
The second is a review of efficiency concepts that students should learn in intermediate microeconomics. (It turned out that many students hadn't previously seen the Edgeworth Box, the topic of the second worksheet.) It has the interactive graphs so you might try this one too, at least answer a few questions correctly and see how the graph updates when you do. This is achieved by having the series that generate the graph to be conditional on whether the student has answered the appropriate question correctly. For example, this is the entry in the cell that gives the series name for the series called Demand Curve.
=IF(H32="Correct","Demand Curve"," ")
Let's deconstruct this one entry. We'll leave it to the reader's imagination to understand how the rest of that series and other series are constructed. In this case the student puts an answer into cell G32. The feedback the student gets is in cell H32. The content of cell H32 has one of three values. It is blank if the student has yet to put an answer in G32. It is Incorrect if the student has put in a wrong answer in cell G32. And it is Correct if the student has put in a correct answer in cell G32. The quotes you see denote a text string between the left quote and the right quote. Absent the quotes Excel interprets entries numerically. The IF statement above can then be read as: if the student answers the question correctly then title the series Demand Curve, otherwise title the series with a blank string.
The student doesn't see this IF statement. It comes from cell AC34. But that cell is locked, the font in the cell is white so can't be distinguished from the background, and the worksheet is password protected so the student can't access the cell's content. I hope this gives a little sense of how the worksheet is constructed. There are quite a few other graph plotting tricks that are used, so things get labelled in a readable way to relate what the student is answering to what is being plotted in the graph. I won't cover those tricks here. But I will say that others can be taught them so that if this approach is liked, it can be replicated after some instruction on how to do it.
The real key to whether this approach provides effective instruction is not the cutesy use of technology, however. It is the quality of the authoring. Do the students see the value add to them from doing the homework? One critical idea here is that the homework is not assessing what students should have already learned elsewhere. The learning should be happening while the student answers the questions. In that sense, the aim of the homework is to be like play in getting the student familiar with the issues and to encourage her to spend enough time on the content to get some familiarity with it. The further aim is to convince the student that the models provide insight that wouldn't be apparent from a text only approach. And, of course, I hope student gets some insight into the underlying economics.
It is hard to author this way, no doubt. But one does develop facility with the approach over time. So the bigger issue with the writing is coming up with what one wants to do conceptually and then how to illustrate the concepts. The actual placing entries into the cells then goes reasonably quickly after that.
I am optimistic about the approach and the early feedback I've gotten from the students indicates they like this too. We'll see if I can keep it up and sustain their interest in the course this way.
The third workbook is about coordination problems and coordination mechanisms. It's a live homework now. You are welcome to try it, but please don't submit your key. It is the first homework with content relevant for our class that they likely haven't seen in other classes.
I believe this approach can work in other courses that have some math in them but that aren't only about the math. Perhaps they could work in math only classes but, but the math instructors I know tend to favor their own tools (not Excel). Way back when I was interested in this sort of thing so the assessment would happen on the local computer rather than on the LMS server and thereby not clog the server near a homework deadline for a big class. That issue is somebody else's problem now. My interest now is the blend of presentation and assessment delivered in homework in a highly interactive way, one that students find compelling. The authoring environments provided to most instructors don't allow for his possibility. But these Paris in a Bottle Excel Exercises are meant to show it is quite possible to deliver very rich content in this way. We should be going after that in what we give our students, especially the implicitly math phobic ones, who won't make good progress with more traditional methods.
Friday, September 14, 2012
Files not going away in spite of the Cloud/Google service changes impinging on my use
One senses a competition heating up between Box, Dropbox, Google Drive, and other services for document sharing like Scribd and Slideshare. For the first three, the behavioral problem that the services appear to be trying to solve is how to manage one's files when using multiple devices. This is a personal computing issue and the key seems to be to use the cloud in conjunction with an application on each device that enables syncing of the file collection. The old technique, tried but not true, of sending a copy of the file as an email attachment just doesn't cut it anymore.
I mentioned the other services, Scribd and Slideshare, because they suggest a different solution to the issue, at least a different solution for the class of files that you'd call documents. That alternative is to convert the documents into Web readable form and view them (and edit them too) in a browser. Google's approach seems somewhere in between the two or perhaps might better be thought of as the union of the two. It had a further interesting aspect to it. You could author directly in the Google environment. As such it provided competition for Microsoft Office, and for free. Previous efforts at competition with Microsoft in this arena - Star Office, Open Office - perhaps created some following among uber techies but were a failure at getting a mass following.
The ability to use only a browser and yet have substantial functionality of this sort appealed to my sensibility. Alas, Apple's approach with the iPhone doomed the browser only approach as something the crowd would embrace. Google Drive, which too requires a dedicated app, is just one more lance into an already bloodied soldier returning home from a losing battle.
In my own use, I have only partially approximated the Web only ideal. In composing blog posts like this one I have moved to doing so in the Blogger text box rather than in Word or some alternative. This move was precipitated when the Word publish to Blogger function stopped working. But I've found since that I actually have a preference for doing it this way. Since the html is comparatively clean, I can go from the Compose view to the HTML view and edit it, which I do for example when inserting a cutout from Kwout. I believe now that the presence of a grammar checker hurts my proofreading, since it encourages laziness that getting rid of the green and blue squiggles is sufficient. So I prefer not to have that functionality. Further, on the formatting of the document, not using a Word processor makes you more sensitive to how the document will appear in a browser. I typically don't use much formatting at all but when I do I'm thinking not of replicating a Word document but how the Web page will appear.
On the other hand, when I need a lot of formatting - such as when doing a document with a fair amount of math in it, then I still use Word and make a PDF from that. And folks who know me are aware that I rely on Excel a lot. I use Google Spreadsheet, but mainly in conjunction with Google Forms. When I do my econ stuff in a spreadsheet, I need the real Excel and take advantage of functions there to make my graphs highly interactive.
So, if somebody like me with an inclination for the Web only approach nonetheless relies on the dedicated applications more than they care to admit, I suppose it is not surprising that the Box, Dropbox, etc. way of solving the problem seems to be winning now. Nonetheless, in my heart I'm saddened that Google with Google Docs/Drive is following along rather than reaffirming Web only.
* * * * *
I have multiple Google accounts. The two I use most prominently are a personal account for such things as this blog and a prof.arvan account that I use in my econ teaching and now with communicating externally to a non U of I student audience about learning objects I've made --- this YouTube channel where the bulk of the videos are screen capture movies with voice over based on these Excel spreadsheets, and this fledgling experiment on conducting online office hours for this external audience. Until now I've managed these accounts by using a different browser for each - Firefox for the personal account and Chrome for the prof.arvan account. That has worked remarkably well.
I should add the following. When I was working I had three computers that I composed on - my desktop machine at work, my laptop/tablet pc from work, and my desktop machine at home. I'm now down to having one machine for composing, my home desktop machine. If I had a second computer for composing, the thing I'm going to complain about would not be a problem. I could manage it by using different machines. I do have an iPad now, but it is not the right device for me as an author. In a Web only world it might be, but otherwise not, especially with my use of Excel. (And though there is a cloud version of it, when I tried that at home it was just too slow.)
Google Drive does not allow multiple personal accounts on one machine. Apparently it does allow multiple accounts if they are in different domains. For example, if you have a Google Apps account through your institution and a personal Gmail, then you can manage both accounts with the Google Drive app on a single computer. Not being a real techie, I can't tell whether this inability to manage multiple personal accounts is only for technical reasons or not. This move is forcing me to make an adjustment that I'd prefer not to make. If I ultimately discover that not accommodating multiple personal accounts was a policy decision rather than a technical one, I'll be even more irked. In the tit-for-tat thinking that preoccupies one's mind when in such a state, the thought would be that if Google is going to screw me....
A few years ago I had a column in the now defunct Educause Quarterly. The pieces are preserved in Educause Reveiw Online. This first essay entitled Innovations and Tragic Tories was meant to take a dual perspective approach - campus providers of IT services, on the one hand, and users of IT services, on the other, and discuss the conundrums that arise when older service offerings are replaced or cancelled without replacement. The issue was how best to manage these conundrums. In the piece I argued that the CIO or other high IT officers would need to put their own reputations on the line to facilitate effective transitions, particularly if the service changes were dictated by budgets cuts rather than the usual (not so) planned obsolescence.
The parallel between that case and case of Google is not exact but I think it is sufficiently similar to make the connection. Ten years ago Google was the Luke Skywalker of the Internet, with Microsoft in the role of Darth Vader. It seems that as we grow older each of us turn into our fathers. Is that what is happening here?
The move from Google Docs to Google Drive is not the only area where I'm being forced to accommodate service changes by Google. After they announced they were shutting down iGoogle next year, I wrote this post on Replacing iGoogle. Via that I discovered SaveiGoogle.org. They have a blog and in it they linked to my post, generating roughly four times the number of hits a post of mine usually gets. It's certainly not sufficient volume to make Google reconsider their decision from a business perspective, but it was enough to convince me that I'm not the only one having these sort of thoughts.
However, unlike most of the others I did spend a significant amount of my work life as a leader in learning technology, so rather than simply a gut reaction to harp at Google, I've also been asking whether I have a responsibility too and that the right thing for me to do would be to establish a prof.arvan domain and get a prof.arvan account with Dropbox or Box for the file sharing. I can see the argument, but so far I'm not there. Here's why.
I didn't plan or intend to get a bunch of external users with the YouTube videos. I went that route mainly because YouTube had developed the ability to automatically put in the timings for the captions once a transcript was uploaded and the further exotic ability to translate the captions into other languages. I was committed to captioning my videos, so that was the focus. I only discovered the external use after the fact, pure serendipity in my view. And then I learned that the YouTube search engine rather than the Google search engine was the main driver for the serendipity. So on the video part, it seems that YouTube is still the way to go and I don't want to abandon that.
Then there is that these other services are not free and though I can afford to pay their fees, it doesn't make sense to me to give my stuff away freely to others if I have to incur real out-of-pocket expenses myself in the process. Surely, that is an approach that doesn't scale and doesn't replicate. The way I do things may be idiosyncratic, but I always hope that others might try something similar.
Further, there is the idea that there has to be a lot of intentionality and knowing ahead of time it will work if you go the personal domain route. It surely makes sense for Khan Academy. It may make less sense for the rest of us who have orders of magnitude less market share. And, at least in my case, I'm not doing this for the off chance that demand for my stuff will explode. I'd be quite content if the volume remains low, as long as the demand is steady.
Implicitly, Google seemed to be supporting my efforts. It might not have been aware of the particular use case but by being Web based and free it was leaving that to the users. It was simply being a master enabler of whatever the users came up with. Now it seems the Web based part of the promise is breaking. And that makes you ask, what other parts will break in the future?
Maybe it's time for me to become a WordPress guy.
I mentioned the other services, Scribd and Slideshare, because they suggest a different solution to the issue, at least a different solution for the class of files that you'd call documents. That alternative is to convert the documents into Web readable form and view them (and edit them too) in a browser. Google's approach seems somewhere in between the two or perhaps might better be thought of as the union of the two. It had a further interesting aspect to it. You could author directly in the Google environment. As such it provided competition for Microsoft Office, and for free. Previous efforts at competition with Microsoft in this arena - Star Office, Open Office - perhaps created some following among uber techies but were a failure at getting a mass following.
The ability to use only a browser and yet have substantial functionality of this sort appealed to my sensibility. Alas, Apple's approach with the iPhone doomed the browser only approach as something the crowd would embrace. Google Drive, which too requires a dedicated app, is just one more lance into an already bloodied soldier returning home from a losing battle.
In my own use, I have only partially approximated the Web only ideal. In composing blog posts like this one I have moved to doing so in the Blogger text box rather than in Word or some alternative. This move was precipitated when the Word publish to Blogger function stopped working. But I've found since that I actually have a preference for doing it this way. Since the html is comparatively clean, I can go from the Compose view to the HTML view and edit it, which I do for example when inserting a cutout from Kwout. I believe now that the presence of a grammar checker hurts my proofreading, since it encourages laziness that getting rid of the green and blue squiggles is sufficient. So I prefer not to have that functionality. Further, on the formatting of the document, not using a Word processor makes you more sensitive to how the document will appear in a browser. I typically don't use much formatting at all but when I do I'm thinking not of replicating a Word document but how the Web page will appear.
On the other hand, when I need a lot of formatting - such as when doing a document with a fair amount of math in it, then I still use Word and make a PDF from that. And folks who know me are aware that I rely on Excel a lot. I use Google Spreadsheet, but mainly in conjunction with Google Forms. When I do my econ stuff in a spreadsheet, I need the real Excel and take advantage of functions there to make my graphs highly interactive.
So, if somebody like me with an inclination for the Web only approach nonetheless relies on the dedicated applications more than they care to admit, I suppose it is not surprising that the Box, Dropbox, etc. way of solving the problem seems to be winning now. Nonetheless, in my heart I'm saddened that Google with Google Docs/Drive is following along rather than reaffirming Web only.
* * * * *
I have multiple Google accounts. The two I use most prominently are a personal account for such things as this blog and a prof.arvan account that I use in my econ teaching and now with communicating externally to a non U of I student audience about learning objects I've made --- this YouTube channel where the bulk of the videos are screen capture movies with voice over based on these Excel spreadsheets, and this fledgling experiment on conducting online office hours for this external audience. Until now I've managed these accounts by using a different browser for each - Firefox for the personal account and Chrome for the prof.arvan account. That has worked remarkably well.
I should add the following. When I was working I had three computers that I composed on - my desktop machine at work, my laptop/tablet pc from work, and my desktop machine at home. I'm now down to having one machine for composing, my home desktop machine. If I had a second computer for composing, the thing I'm going to complain about would not be a problem. I could manage it by using different machines. I do have an iPad now, but it is not the right device for me as an author. In a Web only world it might be, but otherwise not, especially with my use of Excel. (And though there is a cloud version of it, when I tried that at home it was just too slow.)
Google Drive does not allow multiple personal accounts on one machine. Apparently it does allow multiple accounts if they are in different domains. For example, if you have a Google Apps account through your institution and a personal Gmail, then you can manage both accounts with the Google Drive app on a single computer. Not being a real techie, I can't tell whether this inability to manage multiple personal accounts is only for technical reasons or not. This move is forcing me to make an adjustment that I'd prefer not to make. If I ultimately discover that not accommodating multiple personal accounts was a policy decision rather than a technical one, I'll be even more irked. In the tit-for-tat thinking that preoccupies one's mind when in such a state, the thought would be that if Google is going to screw me....
A few years ago I had a column in the now defunct Educause Quarterly. The pieces are preserved in Educause Reveiw Online. This first essay entitled Innovations and Tragic Tories was meant to take a dual perspective approach - campus providers of IT services, on the one hand, and users of IT services, on the other, and discuss the conundrums that arise when older service offerings are replaced or cancelled without replacement. The issue was how best to manage these conundrums. In the piece I argued that the CIO or other high IT officers would need to put their own reputations on the line to facilitate effective transitions, particularly if the service changes were dictated by budgets cuts rather than the usual (not so) planned obsolescence.
The parallel between that case and case of Google is not exact but I think it is sufficiently similar to make the connection. Ten years ago Google was the Luke Skywalker of the Internet, with Microsoft in the role of Darth Vader. It seems that as we grow older each of us turn into our fathers. Is that what is happening here?
The move from Google Docs to Google Drive is not the only area where I'm being forced to accommodate service changes by Google. After they announced they were shutting down iGoogle next year, I wrote this post on Replacing iGoogle. Via that I discovered SaveiGoogle.org. They have a blog and in it they linked to my post, generating roughly four times the number of hits a post of mine usually gets. It's certainly not sufficient volume to make Google reconsider their decision from a business perspective, but it was enough to convince me that I'm not the only one having these sort of thoughts.
However, unlike most of the others I did spend a significant amount of my work life as a leader in learning technology, so rather than simply a gut reaction to harp at Google, I've also been asking whether I have a responsibility too and that the right thing for me to do would be to establish a prof.arvan domain and get a prof.arvan account with Dropbox or Box for the file sharing. I can see the argument, but so far I'm not there. Here's why.
I didn't plan or intend to get a bunch of external users with the YouTube videos. I went that route mainly because YouTube had developed the ability to automatically put in the timings for the captions once a transcript was uploaded and the further exotic ability to translate the captions into other languages. I was committed to captioning my videos, so that was the focus. I only discovered the external use after the fact, pure serendipity in my view. And then I learned that the YouTube search engine rather than the Google search engine was the main driver for the serendipity. So on the video part, it seems that YouTube is still the way to go and I don't want to abandon that.
Then there is that these other services are not free and though I can afford to pay their fees, it doesn't make sense to me to give my stuff away freely to others if I have to incur real out-of-pocket expenses myself in the process. Surely, that is an approach that doesn't scale and doesn't replicate. The way I do things may be idiosyncratic, but I always hope that others might try something similar.
Further, there is the idea that there has to be a lot of intentionality and knowing ahead of time it will work if you go the personal domain route. It surely makes sense for Khan Academy. It may make less sense for the rest of us who have orders of magnitude less market share. And, at least in my case, I'm not doing this for the off chance that demand for my stuff will explode. I'd be quite content if the volume remains low, as long as the demand is steady.
Implicitly, Google seemed to be supporting my efforts. It might not have been aware of the particular use case but by being Web based and free it was leaving that to the users. It was simply being a master enabler of whatever the users came up with. Now it seems the Web based part of the promise is breaking. And that makes you ask, what other parts will break in the future?
Maybe it's time for me to become a WordPress guy.
Wednesday, September 12, 2012
The Regular Google Docs and the Campus Google Apps
The public part of my course site (I will use `Moodle for private communication with the students and to keep the class grade book) is based on Blogger. I've been using Blogger for such a long time that I know quite a few little tricks with it. Among those are the good sidebar gadgets to use. One of those is for Google Calendar. The Upcoming Class Activities item gives the full text description for the five most proximate calendar items. Unfortunately, Google Calendar doesn't allow hyperlinks in those text descriptions. (I'd be in heaven if they did.) You could then link to readings or other files that students need that way. I have students do homework in Excel. So I need a way for them to get at the file at the right time. More about that in a moment.
While you can't do hyperlinking in the text, Google Calendar does allow insert of file attachments, if those attachments are in Google Docs (now Google Drive). Further since Google Docs allows upload of any file type and leaving it in its native format, this seemed like not a bad solution. You teach the students to right click on the entry in the sidebar and then open the full calendar entry in a new tab. That gives access to the file attachment. Since all the files I use for teaching I make available to the general public, anyone should be able to access my class content that way, or so I thought.
My experience this past week has shown otherwise. I got an inordinate number of requests to my prof.arvan gmail account to share a homework file with students. I sent email back to these students saying the file didn't need to be shared since it was publicly available. These students then reported to me that they couldn't access it.
I was initially confused by this but now I surmise the following, though I'm still not 100% sure it's what is going on. These students are logged into their campus email, which gives them access to Google Apps for the campus. For some reason that creates a firewall with commercial Google Docs, even for files that are supposedly publicly available in the commercial version. Why this is happening, I have no idea. But that it is happening seems evident.
The immediate work around is to use the new Campus Box service for the files (and still use Google docs for those student who don't use campus email, which seems like a large fraction of them.) Files made publicly available in Box, should be publicly available. I can put the url into the calendar text description. But they'll have to copy and paste it. C'est la vie.
I'm less sure of the longer term solution. The Campus now seems to be offering a WordPress blog service. I could see using WordPress and Box in conjunction. I'm not quite sure what would replace Google Calendar in this alternative. I think some scheduling program is an absolute must. Students are so driven by deadlines in their behavior that they need reminders of them quite regularly.
Blogger remains appealing to me in part because of how it interacts with Google Calendar. (Also, this semester I'm having students blog with aliases that I've created and so far that seems to be working. Go down the sidebar to the item on Student Blogs. I'm less sure I can do that with a Campus service.) These may seem like piddly little issues in themselves. But resolving them is the difference between having this sort of approach work or not.
So I'm more than a little crabby about the snafu I've had with students not being able to access my Google Docs. I thought I had designed a scheme that worked. Not quite.
While you can't do hyperlinking in the text, Google Calendar does allow insert of file attachments, if those attachments are in Google Docs (now Google Drive). Further since Google Docs allows upload of any file type and leaving it in its native format, this seemed like not a bad solution. You teach the students to right click on the entry in the sidebar and then open the full calendar entry in a new tab. That gives access to the file attachment. Since all the files I use for teaching I make available to the general public, anyone should be able to access my class content that way, or so I thought.
My experience this past week has shown otherwise. I got an inordinate number of requests to my prof.arvan gmail account to share a homework file with students. I sent email back to these students saying the file didn't need to be shared since it was publicly available. These students then reported to me that they couldn't access it.
I was initially confused by this but now I surmise the following, though I'm still not 100% sure it's what is going on. These students are logged into their campus email, which gives them access to Google Apps for the campus. For some reason that creates a firewall with commercial Google Docs, even for files that are supposedly publicly available in the commercial version. Why this is happening, I have no idea. But that it is happening seems evident.
The immediate work around is to use the new Campus Box service for the files (and still use Google docs for those student who don't use campus email, which seems like a large fraction of them.) Files made publicly available in Box, should be publicly available. I can put the url into the calendar text description. But they'll have to copy and paste it. C'est la vie.
I'm less sure of the longer term solution. The Campus now seems to be offering a WordPress blog service. I could see using WordPress and Box in conjunction. I'm not quite sure what would replace Google Calendar in this alternative. I think some scheduling program is an absolute must. Students are so driven by deadlines in their behavior that they need reminders of them quite regularly.
Blogger remains appealing to me in part because of how it interacts with Google Calendar. (Also, this semester I'm having students blog with aliases that I've created and so far that seems to be working. Go down the sidebar to the item on Student Blogs. I'm less sure I can do that with a Campus service.) These may seem like piddly little issues in themselves. But resolving them is the difference between having this sort of approach work or not.
So I'm more than a little crabby about the snafu I've had with students not being able to access my Google Docs. I thought I had designed a scheme that worked. Not quite.
Sunday, September 09, 2012
Sensibility in Retreat
Where was Anthony Downs' spirit at the Party Convention,
With moderates absent and only Bruni giving mention?
Many Midwest Democrats don't seem to like the President.
That must be the reason all these candidates are hesitant.
For the ailing economy apparently no way out,
There's no will for real solutions; pols on each side simply pout.
Ideological purity, toeing the Party line,
Makes true believers happy yet hastens the nations' decline.
With moderates absent and only Bruni giving mention?
Many Midwest Democrats don't seem to like the President.
That must be the reason all these candidates are hesitant.
For the ailing economy apparently no way out,
There's no will for real solutions; pols on each side simply pout.
Ideological purity, toeing the Party line,
Makes true believers happy yet hastens the nations' decline.
Wednesday, September 05, 2012
Upward Mobility or Misdirection
There is much irony in that the Republicans were supposed to run on the plank, "we're not Obama" but in fact it's the Democrats who are running on "we're not Romney."
It's fine to say you're for the middle class. But the important thing is to talk about the policies needed to bolster their welfare. The situation is not symmetric between the Democrats and the Republicans. The Democrats want government to help ordinary people. They need to say how that will happen.
The economy desperately needs a further large and sustained stimulus. That should be the number one policy objective. The Republicans have used scare tactics about the National Debt to confuse the public on this issue. This convention should be about articulating precisely that and that we need an active fiscal policy now.
Per capita GDP has fallen since the housing bubble burst. There won't be much in the way of upward mobility until per capita GDP starts to rise again on a consistent basis. In the current political environment it seems the burden is on the Fed to provide stimulus. But we need fiscal policy now. Interest rates are already extraordinarily low. What we need is spending.
We are unlikely to get it, even if President Obama is reelected. Congress will remain obstructionist. This should be at the core of what the convention is about. This convention should be more about changing the composition of Congress than it is about reelection of the President. There is an opportunity here to be much more aggressive in articulating what government should do and in explaining why it hasn't been doing it of late.
I wonder if we'll hear any of this tonight.
It's fine to say you're for the middle class. But the important thing is to talk about the policies needed to bolster their welfare. The situation is not symmetric between the Democrats and the Republicans. The Democrats want government to help ordinary people. They need to say how that will happen.
The economy desperately needs a further large and sustained stimulus. That should be the number one policy objective. The Republicans have used scare tactics about the National Debt to confuse the public on this issue. This convention should be about articulating precisely that and that we need an active fiscal policy now.
Per capita GDP has fallen since the housing bubble burst. There won't be much in the way of upward mobility until per capita GDP starts to rise again on a consistent basis. In the current political environment it seems the burden is on the Fed to provide stimulus. But we need fiscal policy now. Interest rates are already extraordinarily low. What we need is spending.
We are unlikely to get it, even if President Obama is reelected. Congress will remain obstructionist. This should be at the core of what the convention is about. This convention should be more about changing the composition of Congress than it is about reelection of the President. There is an opportunity here to be much more aggressive in articulating what government should do and in explaining why it hasn't been doing it of late.
I wonder if we'll hear any of this tonight.
Subscribe to:
Posts (Atom)