February 2012
12 posts
I want to do this in a class....
What a neat way of combining two textbooks to get a novel course design (which meshes with current theories of interleaving):
In an effort to maximize spacing and encoding variability, Robert Bjork once taught an honors introductory psychology course twice in one term. Up to the point of the midterm, the basic concepts of introductory psychology were covered using a textbook that adopted a...
Divided Attention During Lecture
I’ve been having some fun reading Bjork and his followers on elements of instruction. It’s good stuff! This comes from Successful Lecturing: Presenting Information in Ways That Engage Effective Processing by Patricia Ann de Winstanley & Robert A. Bjork:
In addition to its having a strong negative impact on encoding, divided attention has been shown to have much larger effects on...
Concept Inventories and Dan Meyer's Linear...
I’ve talked a bit in the past about good concept inventory questions — questions that address difficult conceptual questions but have black and white answers and don’t require any special vocabulary to answer.
Dan Meyer’s Linear Modeling exercise [PDF] is a good example. The first question has a specific answer, and answering it requires the right set of intuitions about...
Comparing Electoral Behavior
From the Utne Reader, in an article showing that we ” are segregating [our]selves politically and geographically” in the U.S. :
“In 1992, 38 percent of Americans lived in counties decided by landslide elections; by 2004, that figure was 48 percent.”
One thing that jumps out at me immediately is that elections are very hard to compare to one another. In this case,...
Fireside Tutorials and Punk Economics
What do we call this genre of videos, these informal explanations by Khan Academy, RSA:Animate, Common Craft, Vi Hart, and others — these sit across the desk from you and talk things through? I have no idea. But I’m fascinated with the form, and how rethinking video this way makes a lecture seem more like tutoring — even when (as in the case of RSA:Animate) the material is often...
Obesity and C-Section StatLit Materials →
Some stuff from Thursday’s class. Here’s the facilitator’s notes as well, if you want to run this in your own class.
It’s a sort of “case-study lite” approach. I gave the students the following in a packet:
An article talking about research which showed people born by C-section are at a 50% greater risk of obesity than those that weren’t, and...
Hill's nine criteria for causal association
Sir Austin Bradford Hill’s classic article on the characteristics of a causal relationship is well worth a read, and is still one of the most concise lists of what to look for in any research you read. Here’s a summary of what helps us make the leap from association to causation:
Strength (is the risk is large)
Consistency (the results have been replicated, by different researchers...
Problems of Definition: Elsevier's Prices
The recent boycott of Elsevier provides us with a great quote for use in a statistical literacy class. People are boycotting for a number of reasons, particularly because of the high cost of the “bundles” Elsevier sells.
Claiming that their journals are some of the cheapest in the industry, an Elsevier rep states:
“Over the past 10 years, our prices have been in the lowest...
January 2012
19 posts
Ecological Validity
Term of the day: ecological validity.
Ecological validity is a pretty big concern in ed psych, obviously. But I’ve also just read an interesting paper in Health, Risk, and Vulnerability which talks about the ecological validity of psychiatric assessment of criminals being treated for mental illness. The idea there is that many prisoners that do poorly in the highly restrictive environment...
A good example of age as confounder
From The Numbers behind Numb3rs:
Cobb illustrated the distinction by means of a famous example from the long struggle physicians and scientists had in overcoming the powerful tobacco lobby to convince governments and the public that cigarette smoking causes lung cancer. Table 2 shows the mortality rates for three categories of people: nonsmokers, cigarette smokers, and cigar and pipe smokers.
...
Incidence, Prevalence, and the Obama Job Record
Since the statistics class I teach is supposed to be integrative — that is, to show connections between various disciplines and other aspects of life — I’m always on the lookout for ways to jury-rig an understanding from one domain to understand another. I think I just found a neat example.
But first, look at these two different stories of the Obama record on jobs:
To the...
'Adrift' in Adulthood: Students Who Struggled in... →
From the article:
Here is what they found: Graduates who scored in the bottom 20 percent on a test of critical thinking fared far more poorly on measures of employment and lifestyle when compared with those who scored in the top 20 percent. The test was the Collegiate Learning Assessment, or CLA, which was developed by the Council for Aid to Education.
The students scoring in the bottom...
Infant mortality and choice of a base
If I have 10 kids in my class and two failed last year and one failed this year, I can say two equivalent things:
50% less students failed my course this year
10% more of my students passed.
The odd thing is most students refuse when looking at such figures to believe they are equivalent statements. In fact, they are prone to believe that if
10% more of my students passed, then
There were...
Tutoring at Scale Sighting
From The Chronicle, Tenured Professor Departs Stanford U., Hoping to Teach 500,000 Students at Online Start-Up:
Eventually, the 200 students taking the course in person dwindled to a group of 30. Meanwhile, the course’s popularity exploded online, drawing students from around the world. The experience taught the professor that he could craft a course with the interactive tools of the Web that...
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On Sex After Prostate Surgery, Confusing Data... →
A classic problem of term definition from the NYT (somewhat older article):
A notable study in 2005 showed that a year after surgery, 97 percent of patients were able to achieve an erection adequate for intercourse. But last month, researchers from George Washington University and New York University reviewed interim data from their own study showing that fewer than half of the men who had...
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Are we winning or losing the "War on Cancer"?
If your answer was that war is the wrong metaphor, you win the prize, I suppose. Still, I found this exercise from a medical stats textbook rather interesting:
17.1. A major controversy has occurred about apparent contradictions in biostatistical data as researchers try to convince Congress to allocate more funds for intramural and extramural investigations supported by the NIH. Citing improved...
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How Visa Predicts Divorce →
From TDB:
Hunch then looks for statistical correlations between the information that all of its users provide, revealing fascinating links between people’s seemingly unrelated preferences. For instance, Hunch has revealed that people who enjoy dancing are more apt to want to buy a Mac, that people who like The Count onSesame Street tend to support legalizing marijuana, that pug owners are often...
Udacity and the future of online universities →
Felix Salmon on Sebastian Thrun, the open course runner extraordinaire who built the Stanford AI course:
Thrun was eloquent on the subject of how he realized that he had been running “weeder” classes, designed to be tough and make students fail and make himself, the professor, look good. Going forwards, he said, he wanted to learn from Khan Academy and build courses designed to make as many...
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The Numbers Game
We often talk of social statistics, especially those that seem as straightforward as age, as if a bureaucrat were poised with a clipboard, peering through every window, counting; or, better still, had some machine to do it for them. The unsurprising truth is that, for many of the statistics we take for granted, there is no such bureaucrat, no machine, no easy count, we do not all clock in, or...
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Keynes, Anti-Semite? Really?
Pardon the intrusion — but I find this interesting. There’s a diary entry of Keynes being circulated around that supposedly proves Keynes was an anti-Semite. This is meant to be a brilliant rebuttal to Paul Krugman’s “Keynes was Right” column on how Keynes’s theoretical model of macroeconomics has been vindicated.
In some ways it doesn’t matter. Milton...
December 2011
22 posts
Why the I Love Charts post is the most beautiful... →
There’s so much to like in this post. It starts with nuanced exploration of feminism, terminology, and privilege, but ends as a reflection of the difficulties of staying a good person on the internet, especially when you run a site.
Dealing with trolling makes you hard and reactive. Even non-trolls delight in deliberate misunderstandings. False outrage is the norm. As the level of...
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Klout wins for this year's stupidest bar chart
Check it out here:
http://blog.infoadvisors.com/index.php/2011/12/22/stupidest-bar-chart-of-2011-congrats-klout/
I’m not sure how you trust a company who claims to have some super-secret statistical insight when they put out things like this.
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A Herd Immunity to Nonsense
Mark Pagel on the internet and our cultural evolution:
A tiny number of ideas can go a long way, as we’ve seen. And the Internet makes that more and more likely. What’s happening is that we might, in fact, be at a time in our history where we’re being domesticated by these great big societal things, such as Facebook and the Internet. We’re being domesticated by them,...
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Cognitive Bias and Education as a Public Good
A strange but true exhortation from Dan Kahneman, the guy who, with Amos Tversky, basically invented the field of cognitive bias. After forty years of looking into the weird world of bias he says the only effective way to get around your own biases is to create a society of people skilled enough to correct you:
From the end of Thinking, Fast and Slow:
What can be done about biases? How can we...
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Evidence-Based and the Marginal Cost of Zero
If you can conceive of a solution to a problem that has a marginal cost of zero due to cheap replication and economies of scale, then that’s good. If you’re doing that by going into the digital space, where cost of experimentation is low, even better.
Many elements of education are best seen through the marginal cost of zero lens, and it’s that dream of essentially free...
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Semantic Mapping vs. Pictorial Cues
From A Theory-Based Meta-Analysis of Research on Instruction by RJ Marzano:
The next two techniques displayed in Table 7.2 employed the information processing function of idea representation. Techniques that provided students with metacognitive strategies for using visual memory had an effect size of 1.04, indicating a percentile gain of 35 points. Presumably, these strategies help students...
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Stanovich on Conflict and Critical Thinking
Well, actually the Hitchcock review of Stanovich:
What types of people succeed in overriding interactional intelligence in conflict situations? As one might expect, subjects with greater cognitive ability (as measured by SAT Total scores) were more likely to do so. But so were those with the dispositions characteristic of an ideal critical thinker: even after controlling for differences in...
Openness as a Privilege Multiplier and the MIT...
This is pretty huge news:
Millions of learners have enjoyed the free lecture videos and other course materials published online through the Massachusetts Institute of Technology’s OpenCourseWare project. Now MIT plans to release a fresh batch of open online courses—and, for the first time, to offer certificates to outside students who complete them.
The credentials are part of a new,...
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Base Rate, Revisited
Reading Dan Kahneman’s Thinking Fast and Slow, and I can tell very early in it’s going to be excellent.
The following Kahneman insight is an old saw of research on statistical intuition by now, but was revolutionary when he and Tversky came up with it in the early 70s. I thought I’d share it for those not familiar with it:
As you consider the next question, please assume that...
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Moonwalking with Einstein
Just finished Joshua Foer’s book Moonwalking with Einstein, one of the most amusing books I’ve read in a while. I’d highly recommend it to anyone, just based on the style of his writing alone, which strikes me as Jonah Lehrer as written by Sarah Vowell (of The Wordy Shipmates period, not Assassination Vacation). But that probably doesn’t really capture it either.
You know...
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Higher Education is Already a Voucher System
Saw this about the K-12 online space today in NYT:
Some teachers at K12 schools said they felt pressured to pass students who did little work. Teachers have also questioned why some students who did no class work were allowed to remain on school rosters, potentially allowing the company to continue receiving public money for them. State auditors found that the K12-run Colorado Virtual Academy...
Badges
Yep.
As Rowin points out that badges ‘draw upon widespread use of badges and achievements in gaming‘ and as somebody who has many badges and achievements in various game systems I can’t help but wonder if some of the problems that have cropped up in games might cross over into the Open Badge Initiative.
David goes on to outline some historical problems with badges. I think badges may be useful...
“The idea that you can just put stuff out there, and that it will magically be...”
– Carol Twigg on Khan Academy
Openness as a Privilege Multiplier
…was the name of the presentation Jim Groom and I originally submitted to ELI 2011. It was going to investigate the tendency of “undirected and unregulated openness to exacerbate inequality both in and out of the classroom” and suggest that this tendency “undermined the social justice claims of openness”.
Jim’s remedy was going to be corporate regulation (and...
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A Statistical Literacy Concept Inventory
Been thinking lots about concept inventories. The key to a good concept inventory is that it tests intuitions, not terminology or formulas. It’s far too easy to pre-test students on a test with unfamiliar vocabulary, spend a semester on vocabulary, then act surprised that students do better at the end of the semester when they finally understand the questions.
A concept inventory should...
Active Learning Not Associated with Student... →
I’ve been collecting these sorts research examples and making an effort to read them thoroughly, partially because I think we’ve become a bit too self-congratulatory on active learning, and partially because you learn more from these failures than yet another paper confirming active learning/constructivism/engaged pedagogy works.
This one is particularly interesting for a couple of...
Juliette Culver is a Freaking Genius
I just decided to give Evernote another try, found my old account active, and spent a couple hours going through my old bookmarks from 2009.
One was to Juliette Culver’s blog, which I’d made a note to myself was brilliant. It is, but more importantly it’s just even-keeled and unpretentious in its brilliance. It cuts through hype like a hot knife through butter.
You should go...