Monday, January 21, 2013
Password Needed
Friday, July 27, 2012
You clicked on a link, so you read this, right? (Or, some thoughts on learning analytics.)
My initial observations of some the issues are how LA, which appears to have the purpose of modeling an individual's performance and then taking some action based on that model, handles complex statistical procedures. Not the most exciting topic for a blog entry, so I'll be brief.
1. What is the process for model selection in an LA model that encompasses a variety of variables? One question that is important to address is the process of model selection. That is, when researchers develop a prediction model, we use a procedure to select the variables that become part of the model. This procedure can be an automated procedure in a software package (such as stepwise model selection) or a deliberate procedure of testing one variable at a time (by hand) to determine the first variable in the model, the second variable, and so on until you have the final model. In LA, how does this happen? Is one model applied to the data regardless of the quality of fit? Is it transparent?
2. We must be careful to avoid saying that prediction models predict an individual's exact performance. There is always uncertainty. Statistics--especially inferential statistics--is a science that embraces error and uncertainty. That is, a prediction model always has some degree of error--and even a good model predicts the average response of some outcome variable. If I say that my prediction model indicates that this student should receive the GPA of 2.9, then I'm assuming that every student is going to have the average outcome. Some will get higher GPAs, some will get lower. If we do LA, we need to make a commitment to helping our colleagues understand the nature of error.
3. In LA from automated systems like LMS's can we be sure of the data we're analyzing? It is tempting to assume that a page view in a content system means that students read that page. Perhaps they did. As researchers, we may need to develop research methods that enable us to learn about the quality of the interaction in a system like an LMS. This can be done with some kind of instrument that asks students more about how they interacted with some electronic resource. Surely, some systems are catching up to this by enabling more interactivity (such as e-textbooks that allow highlighting, note-taking, and sharing of questions with instructors), but we should be skeptical of each variable we consider in a LA procedure.
Friday, June 29, 2012
E-text Unconference (Day 1)
So it's interesting to be at a conference at which there are people who are trying to develop e-textbook platforms and others who want to know where the business of textbooks is headed.
During day 1 of the conference, there was a short presentation by a speaker (a consultant) who talked about the business model for publishers. He argued that the more e-textbooks contain personalized content, the more they will see a business value. It was not clear why. Would publishers want to control the kinds of annotations that students add to e-textbooks or would they use that data to market products? (The speaker referred to this as "differentiated content.") The speaker acknowledged research (from Daytona State College) that showed that students were not enthusiastic about using e-textbooks again after using them for a semester. (One finding of this research was that students preferred renting paper textbooks.)
We voted on which 7 topics to talk about in small groups. Winners were student receptivity, technology platforms, large e-text initiatives--and I forgot the other four. Accessibility was not one of them, and one person in the crowd spoke up and asked where that could be discussed.
At the student receptivity discussion, we talked about a variety of ways that schools have tried to measure students' acceptance (or avoidance) of e-textbooks. There are many librarians here--one says that it is logical for them to work with e-textbooks because libraries have existing relationships with publishers. One large school has conducted a big pilot with an e-textbook provider and found that the majority of students did not want to use an e-textbook again. Also, he said that most of the students (and instructors) did not take advantage of the annotation tools in the e-reader (and there was no relationship between e-text usage and students' grades). They are doing the pilot project again in Fall 2012 because they want to try the system again now that it has been improved. Lots of discussion about how students like paper textbooks, like sharing them with classmates, like selling them back. One finding was that students who did not like the e-textbook felt that it was too distracting to use an e-textbook on their laptop, where they were tempted to facebook, surf the web, chat, etc. There is concern that one e-reader provider would like institutions to use their assessment instruments. Some schools have run into trouble trying to ask their own questions.
So the people involved with companies who develop e-readers have had mixed results...some very enthusiastic people are here, working on their own e-textbook initiative at UIUC. Self publishing of textbooks is big at UIUC. At the table where they talked about initiatives to publish e-textbooks locally, it was all UIUC people. And they did not all know each other. Some UIUC faculty, who have written their e-textbooks, are here to discuss their processes. One chemistry professor has made an online app for chemical equations, which is integrated with his online e-textbook and is working well for him. UIUC seems exceptional in this area of self publishing.
The UIUC undergraduate writing program has developed an e-textbook that they sell to their students. It is an HTML 5 e-textbook with annotation tools, and is accessible. They wanted to build an accessible environment because the companies that make e-readers have often not paid enough attention to accessibility and just put "pictures of textbooks" in their systems that do not meet accessibility standards. To purchase the writing e-textbook (used by all students in undergraduate rhetoric), students go to the textbook store and purchase a scratch-off card with a code that they use to access the e-textbook. They must buy this because the entire course "happens" in the e-textbook--my understanding is that without the e-textbook students cannot complete assignments. They need their own. They can download an epub version that they can use offline, but they won't have access to their annotations. Essentially, there is one e-textbook, and students' annotations live on a database. Each time they log-on, their annotations are pulled down to the e-text they are viewing. (When the developers were building this, they asked a professor if she would want to receive an e-mail each time someone created a highlight. She said no way.)
There isn't much research about this initiative. The head of undergraduate writing program won a national award for this innovation in instruction. They have collected a bunch of surveys that they are still analyzing.
More thoughts to come...
Monday, April 09, 2012
Taking Time to Reflect on Learning in MITx
The designers have been changing small things in the course. It's interesting to see the changes, such as making the current text in the transcript bold when it is spoken in the video. The word "SPEED" now appears next to the buttons for changing the speed of the videos. Other students make suggestions for changing the interface or adding an interface for mobile users. Not me--I'm usually coming from behind…
Which reminds me: three cheers for Wolfram Alpha! When I needed to compute derivatives for the incremental analysis, I only need to type the equation into the computational engine. (My calculator is not good enough for this.) Students were suggesting a variety of tools--such as a math program you can download from Microsoft.
Still, you know you're in deeper waters when you can't solve the problem on your calculator that was sufficient for any other class you've taken. I'm uneasy that I'm avoiding brushing up my calculus--who am I kidding?--whole new coats of math are needed here! I was able to get a decent grade on the homework, but left the last problem untouched because I could only get through half of the lectures for the topic. I am starting to feel the effects of not having the prereqs. I wonder if MITx will have to enforce a certain prior level of knowledge before letting people take a course. Surely I'm not the only one with these problems...but for the moment this may not be a main concern.
The first exam was announced: it will be in the last week of April, and we have 24 hours to complete it once we begin. I've already marked the calendar and told my wife--who, by the way, did a bunch of my chores to give me time to complete MITx work.
Monday, April 02, 2012
Completing Labs in MITx: Thank Heaven for Trial and Error
In Circuits and Electronics, we must complete a weekly lab, an assignment in which we must build a circuit that satisfies certain parameters. Part of the assignment involves getting the appropriate configuration of resistors, wires, and other elements, and another part of the assignment means getting the right values for these elements. It’s a rather safe way to do a lab in basic electrical engineering; I know the only shock I’ll receive is how many times I get the answer wrong.
A lot of my problems with this lab were due to my own ignorance about how to use the circuit sandbox. First, I did not know that you could cross wires in a diagram, which, it turned out, was necessary for the solution to the problem. Of course, crossing wires is acceptable because in an actual circuit, a wire can go over or under a different wire. In my crude diagram, you can see that the red voltage source (the circle) needs to be connected to the red gate (the diamond), so the wire must go over the other gate. I finally found a discussion posting that mentioned that you can cross wires, but another person said that this is in the directions in how to use the sandbox, so I’m to blame for not reading all the directions….One weakness I have is that I am spending more time trying to understand equations than trying to understand the common-sense rules for putting these things together.
But a funny thing is that I was able to get the correct answer by using trial and error to determine the resistance values for these gates. This seems rather unscientific to me, but one hour before the deadline makes me happy for any advantage I may get. And yet, wouldn’t a situation in an actual lab be much much different? For example, at one point, I put the resistance value of a MOSFet so high that I shorted part of the circuit. Now, in the sandbox, who cares, right? But surely this kind of guessing could be dangerous in a real circuit.
One thing I don’t like about the circuit sandbox is that I use “backspace” to delete elements after I’ve selected them. If I hit the button more than once, I go back in the web browser and lose my circuit.
Wednesday, March 28, 2012
Where's the show-your-work-for-partial-credit button in MITx?
But I also came across an answer that included a link to another posting that, I assumed, discussed the concept in more depth. Well, it included a possible answer to the lab. This is another difficulty I have with MITx: avoiding posts that include explicit answers while I am looking for guidance on concepts. I can't unsee those answers, unfortunately.
The Honor Code forbids the posting of answers to graded assignments, but people still post these things. Sometimes people post equations that include every step for solving a problem and only leave out the answer. Really, as a participant in this class, I must keep my own honor code and be judicious when I consult the discussion forum for help with concepts. I phrase questions to make it clear that I just want help understanding a concept.
So my dilemma was whether to use the information I saw--which I would not have understood on my own--or go back to trying the lab by myself. After my poor wife stayed up trying to help me, I decided to give up and take the 0. They drop the two lowest lab scores anyway.
Still, this got me thinking about how MITx does not allow partial credit. I had tried out several different possible answers, and was able to get the correct minimum output voltage. Shouldn't that count for something? The circuit is either correct or incorrect. Perhaps this is a feature of large, free online courses: there aren't the teachers who can scan through thousands of answers to see if the answer deserves partial credit. But I can't help but wonder why it is helpful for students to get a perfect score on a lab or no points at all. Could the labs be broken into several steps in which students could receive credit for completing part of the system correctly?
Today, I looked up the answer to the lab and then posted a question in the discussion forum about the circuit diagram. In ten minutes, I had received two answers from people, and I think I understand my mistake now. And this is what I wanted all the time.
Friday, March 23, 2012
Week 2 in MITx: Feedback in the System
What is the best kind of feedback that you can receive in a massive online course? Lately, I get the red "x" a ton as, there's no denying it, I have a harder time in the class. (Reminder: your answers are assessed immediately by the system: green check means yay!, red x means grr.) The red X propels me to keep studying…I try to think of it as x marks the spot you need to study more.
Feedback has been studied extensively--a significant meta-analysis of feedback was published in 2007 that indicated that cues had the highest effect size. Simple praise had a very small effect size. And feedback about a correct answer had a greater effect size than feedback about incorrect answer--this is particularly difficult feedback to get in a large online course in which I sometimes don't fully understand the answers I'm getting.
The research says to seek out cues, and I could use more cues in my work in MITx. I seem to be able to find them by consulting the discussion forum at just the right time, with a posting that does not give away the entire answer.
More thoughts about peer tutoring in MITx. I posted my first question (about how to identify parallel resistors) and shortly received several responses. In the system, I was able to choose the correct answer--and I was gratified to see that I could choose more than one correct answer. This system of allowing people to accept answers helps to close discussion threads that might continue even after they are useful to people. Being able to accept more than one answer shows that MITx values multiple perspectives and different ways of explaining a concept.
Sunday, March 18, 2012
MITx Homework 1 and Lab 1 are finished. Whew.
Just a reminder: in MITx, the homeworks are online. When you solve a problem, you type the answer into a box, press the "check" button, and--if you're correct--you see a green checkmark beside the field. Some problems are so hard that I do small dances whenever I can get that green checkmark to show up. Most of the time I get the red X, which means, "Try again." The problems have several parts, so you need to get that first answer correct so that it can be plugged into another equation and then your answers fall like dominoes (well, like slowly falling dominoes).
I am grateful, most of all, that the course (so far) has not required any math that is more complicated than algebra. If anything, the problems are hard because you develop a lot of independent equations for different variables (voltage, resistance, current) that you can solve for by a process of substitution. The homework took me a long time--at least 5-10 hours over several days, I think. A lot of my learning seems to happen in the constant process of trial and error--coming up with equations, solving for values, trying out the result.
I have learned that one weakness in the system is that I have gotten several answers by just changing the sign of the value I entered in the box. For this reason, I am still pretty weak on identifying whether currents associated with voltage sources are positive or negative. I have changed x to -x and gone from wrong to right, but I still don't know why I was wrong the first time.
I find that I do get many of the equations or heuristics for solving circuits from the lectures or reading, but the discussion forums contain nuggets of information that I need for solving questions. I look for posts that contain a possible way of thinking about a problem without actually solving the problem. That is hard because part of me just wants the answer.
I am holding my breath that I can continue to succeed despite not having the prereq--I fear that Coulomb's law and electric fields are stalking me in the magnetosphere. But the assumptions of the lumped matter discipline have created a "playground," as the professor calls it, that make things simple (though not easy).
When I checked my grade, I saw that I have earned 3% of the final grade. That 3% is going to be polished and put in a case.
Thursday, March 15, 2012
Creating My Own ZPD?
I did see that one of the T.A.'s posted a response asking people not to post answers in the discussion forums. And by the way, there are some really smart people posting answers; I wonder how many people taking this class have already passed a similar course at another institution.
After seeing the answer I returned to the problem, and began trying out answers. Eventually, I went back to the textbook and read about how to assign the correct sign to a voltage when I am examining elements in a loop. This gave me the key I needed to answer the rest of the questions about how to solve for different elements in the circuit.
I know that some struggling is part of the learning--necessary for keeping that development moving along, to crudely paraphrase Vygotsky. But in MITx, I know that the answers are not far away. It's as easy for me to find the answer as it is to check e-mail. With some fortitude, I was able to figure out the rest of the answers. This makes me think about the zone of proximal development and how this zone is defined in activity when my "more knowledgeable peer" is the online textbook, or a post in a discussion forum. The particular difficulty I have is determining exactly what I don't know, or (in other words) my potential level of development and the right activities for developing a conception that is closer to my potential level. In MITx, I am painfully aware of my actual level of development and am grateful for the tips
How is my understanding of circuits changing--I am learning more about resistance and the different kind of elements within a lumped circuit. It really is simplified by Kirchoff's Laws that turn circuits into junior high math problems, provided you can figure out where to put the sign on currents and voltages, which I am learning to do, though very slowly.
Friday, March 09, 2012
Into the First Unit
Wednesday, March 07, 2012
My progress on MITx: Lab Tutorial
The next few problems in the lab tutorial seem harder, and I will likely take a while to answer them. I have noticed that there is a lot of help in the discussion forums, if I can find the right answer to my question. I have gotten better at using the labels to find answers. (Although sometimes someone posts something weird, such as a question about why the Apple store is down. The moderators shut that one down pretty quick.)
On a side note, I recently received the badge of "Teacher" because I answered someone's question about the function of the check button. This seems more like a "Teaching Assistant" function, but I find myself pleased to have received this acknowledgement. Also, it is nice to help someone else who is working on the course.
While I'm doing this, I keep asking myself what I'm learning, and so far I think I'm learning more about how to operate the interface. Of course, this is very important.
Thursday, April 01, 2010
Diss Progress
Tuesday, March 02, 2010
Stats and Diss
Monday, November 09, 2009
NCPTW Fun
A WC director and one of her tutors presented the results of a survey of faculty that indicated that although faculty value in student writing many of the same aspects that WC tutors value, they often don't consider the WC as a place to get help with those concerns (organization, development of ideas, thesis). It indicated that more communication needs to happen between the WC and faculty.
Throughout the conference there were discussions about the extent to which peer tutors serve as "informants" on the practices of certain instructors. Senior peer tutors know which professors want good thesis statements and which ones want particular fonts. Should peer tutors mediate instructors' expectations of students? Hmm...
The conference organizers chose the concept of leadership and many presenters emphasized how peer tutors can take leadership roles through activities such as developing tutor training programs. One peer tutor talked about how her WC uses recorded conferences to discuss ways to improve conferences.
I attended a good presentation by students and tutors who discussed L2 writers in the WC. A student presented about how she improved writing by working closely with a tutor and yet insisted to others that she will always "write with an accent." She realized that writing well did not mean making her "sound" like a native speaker. Tutors discussed the difficulties that are inherent in tutoring L2 writers and how to navigate them.
Wednesday, September 23, 2009
Inelegant Variation
Tuesday, September 15, 2009
Revisiting Vygotsky and the Forbidden Colors Task
Recently I came across an article that challenges Vygotsky's conclusions about Leontiev's Forbidden Colors Task--conclusions that are included in Mind in Society. In the Forbidden Colors Task, children of different ages were asked 18 questions in four separate tasks. In the first task, the children were asked the questions; in the second, the children were told two color words that they could not use in their answers. The third task included the same constraint as the second task, but the children were also given nine colored cards to aid them. The fourth task was similar to the third.
What were the results? In short, the elementary-aged children made the same number of errors with and without the cards. Older children (8-9 years) had fewer errors when they could use the cards. Vygotsky believed that the results showed three separate stages of development: in the preschool stage, the child could not organize the external tools (the colored cards) to help with the task. In other words, their answers were not mediated by the external tools. Older children were able to use the external tools to mediate their answers, and adults could use internal tools (psychological tools) to mediate their answers.
When van der Veer replicated the study, he added an instruction phase after the fourth task.
The instruction was in both how to use the cards and how to use verbal strategies in the tasks (such as giving "funny" answers, as in the sky is pink). The number of errors severely dropped for all children after the instruction phase, but a closer analysis showed that there was no relation between errors and card use. Thus, the verbal strategy played a an important role. Van der veer also concluded that it is probably wrong to assume that the older children exclusively relied on the external tools--they most certainly brought internal strategies to the task as well. So does this call into question the simplicity of the non-mediated - external tools - internal tools trajectory of development? It is possible that the children in Leontiev's study relied more on the cards because they weren't given instruction in verbal strategies, but Van der veer seems to believe that Leontiev's study was probably not a good one for studying internalization....
Wednesday, August 26, 2009
Language, without its outward garb...
And he defines language. (Who is bold enough to do that?) "Language is a purely human and non-instinctive method of communicating ideas, emotions, and desires by means of a system of voluntarily produced symbols." (8)
Saturday, June 13, 2009
More on Language
In the conference I am transcribing now (with 30) there is a lot talk about the lab procedures, the particular tasks they carried out and the correct way to report those results. The tutor is experienced and provides a lot of guidance about what the correct way to to this is. So much about a conference is correctness, the desire to bring things in line, not to push things out of line. At this stage, though, this is what they wanted. And the conversation is about how to bring ideas into alignment with what is expected of them.
I can't think of a time when they reject the advice, except for a time when an idea was expressed and the consultant was suggesting a different phrasing for that idea. Sometimes the consultant stays out of the process of re-phrasing and lets the students figure it out for themselves.
Wednesday, November 19, 2008
readings
Tuesday, October 14, 2008
Getting through the PhD
Take resume to WCogBeh for feedback.
Make sure you look at the calendar and carve out time for the professional conferences. The application will require three publications so make sure you have some good writing for your app. (You may include a cover letter to explain the contexts of the papers.)
Ask the question (at interview): What does a successful candidate for tenure look like?
Budget for the last year (lots of printing expenses).
The defense of the proposal is more important than the thesis defense.
Make sure you talk to everyone on your committee--not everyone needs to read things, but you should be willing to talk to people about what you are doing.
Finish the dissertation before you take the job--do not go in ABD unless you must.
Go to job talks here and learn about them.
You need to think about the letters that people will write about you when you choose people for your committee.
