Tuesday, July 28, 2009

A Visitor From Redmond, WA

A few days ago, this blog's Feedjit widget showed that a visitor from Redmond, WA (home of Microsoft's headquarters) clicked on this post, "Algebra Challenge". Seeing that, I wondered if someone an interviewer at Microsoft was binging math questions for the company's notorious interview questions1. I happen to have middling math skills myself, but I think this could be an decent interview question, as long as the interviewer just asked the interviewee how he would solve the problem, instead of requiring him to actually solve it (since, the arithmetic is messy, andas commenter J.K. noted in that thread, the actual formula is heavily rounded). The key insight here would be to recognize that the problem can be stated and solved as a system of three equations.

This raises a question I've wondered about in the past, which is to what extent these sorts of questions actually measure intelligence. Maybe it doesn't even matter though, if the questions test for a similarly valuable attribute other than intelligence.

Consider, for example, a couple of word problems I remember from tests I had to take as part of the application process for jobs in the past. Without digging up the exact text of the two word problems this was the gist of them: The first asked how many of each type of coin you would have if you had a certain amount of money in change; the second asked how far apart two individuals would be if one walked so far in one direction and then so far to the left, and the other did the exact opposite. I remember these two word problems for two reasons: I know I got them right, and I know that my getting them right wasn't a reflection of my intelligence or math aptitude. I got the problems right because I had seen them before.

I knew that the first problem could be solved with elementary algebra (using 25x for a quarter, 10x for a dime, and so on), and the second one could be solved with elementary geometry (adding the hypotenuses of the two resulting right triangles). Although these questions didn't measure my intelligence or math aptitude, my getting them right did demonstrate something else: that I had paid attention in math class, or perhaps that I had studied this stuff relatively recently while preparing for a standardized test needed for a graduate degree. So getting those problems right demonstrated either intelligence/aptitude, conscientiousness, or ambition, or some combination of those attributes; and whichever of these attributes a test-taker had would reflect well on him, as far as the employer was concerned.


1I was reminded of this by a conference call I had today with an ABD finance Ph.D. who is doing some consulting for me and one of my web developers. My finance consultant created an algorithm for me, and he was going over it with one of my web developers. My finance consultant assumed that my web developer, who has a bachelors degree in computer science, would have had all the math background necessary to understand the algorithm. My web developer noted that he had a minor in math, in addition to his comp sci degree, but he just wasn't familiar with a particular function the finance consultant specified (an infimum function). I hadn't heard of the function before either, and if a comp sci major/math minor hasn't heard of it, I guess a question based on that function wouldn't be a good one for a Microsoft interviewer.

8 comments:

JK said...

Sounds like you were given an IQ test with your application. Those exact word problems are common IQ test questions, in fact if you go to the Mensa page and do the workout quiz, you will see those questions on there.

And that's one reason of several why I've been skeptical about the ability of some IQ tests to measure native intelligence. A lot of the questions have to do with plugging numbers into a previously memorized formula, or are a type of question that will stump you the first time but not the second. That's not to say I think the tests aren't helpful, they are. But even in the best case scenario, they measure the speed of mental processing, and your ability to do the problems in your head instead of writing them down, more than the quality of reasoning. I think Bill Bradley only scored a 103 on an IQ test, yet he was a Rhodes scholar and I'd consider him to be more intelligent compared to the general population than his test would imply. Also, I have a good friend who, despite my scoring significantly higher in timed standardized tests, I can not for the life of me defeat in chess.

DaveinHackensack said...

I've taken a few different tests as part of job applications in the past. One or two were effectively IQ tests, and some included some personality/psych profile aspects.

I think I may have overstated the case in this post a little re these sorts of questions on IQ-type tests. I may have gotten these problems right because I had seen them before, and others may have had similar experiences with another couple of questions, but overall, I think IQ tests (and thinly disguised, IQ-like tests) are still effective at measuring some sort of "native" potential or intelligence. Otherwise, I would have been able to jack up my math score on the GMAT with all of the studying I did.

There was a comment thread on IQ on the Atlantic's website recently, and I made the analogy between IQ and 40 yard dash times for football players. There are things you can do to marginally improve your performance in either case, but for the most part, you are constrained by your inherent limits. When I was in high school, with a little form running I was able to decrease my 40-time from atrocious to merely awful, but that was all I could do.

It's true that there are some folks who do better in life and in certain fields of endeavor than their IQ scores might suggest. A test score can't predict everything, but it has a lot of explanatory power, which is why it's used so often.

That said, I think some people tend to overemphasize the importance of IQ on an individual basis, particularly when it comes to success in the corporate/business world. Most successful organizations are designed to minimize the amount of thinking required by all except those at the highest levels. As Herman Wouk characterized the Navy in The Caine Mutiny, "a system designed by geniuses to be run by idiots". Even when you're a lone wolf entrepreneur, such as me, you're able to outsource a lot of the intellectual heavy lifting.

OT: did you see my update to the VBDG post below? For some reason, I didn't make the connection until now, but that I-Hub moderator was one of the guys who got indicted on criminal securities fraud recently.

JK said...

Those personality tests could also be an intelligence indicator - anyone stupid enough to answer them honestly gets weeded out.

I don't doubt that IQ measures an important facet of intelligence, but I also doubt it is the end-all-be-all some claim it is. For instance, why are so many high-IQ individuals completely inept at other things most people take for granted? My scores on standardized tests in school (usually, I got the top percentile) have led me to believe I probably have a somewhat high IQ -even though I've never taken a test labeled "IQ test", nor do I care to- yet in high school I could never relate to the nerds who populated my AP classes and I hung out with the athlete crowd (I also played sports myself). I found many of my presumably high-IQ scholastic peers almost incapable of basic tasks such as engaging in interesting conversation, self-perception, or romance for that matter. Could there be a biological tax for having an IQ above a certain threshold? Your comparison to the 40-yard dash is often used, but I wonder how accurate it is. For example, it was easy to identify fast-twitch muscle genes by comparing the genetic profiles of high performance atheletes with regular people, but comparisons of geniuses to normal people have not yielded much that is genetically significant, that I'm aware of. Many in the field of intelligence seem to conflate correlation with causation to make a case for their pre-existant thesis or political goals. Since human thought is probably the most complex biological activity on the planet, I honestly don't expect it to be fully understood for some time, and anyone who claims they have it figured out is most likely full of BS.

While reading a book I mentioned on here, "The Chosen", I noticed Ivy League admins have historically shared my general perception of higher-IQ types. One reason for including extracurricular factors and subjective interviews in the admissions process, besides discrimination against Jews, was that they didn't want their schools to be a collection of "abnormal brain specimens" or "greasy grinds".

Your military quote reminds me of another one "War is too important a matter to be left to the military." by Georges Clemenceau.

I missed the update. I haven't visited IHUB for some time largely for professional reasons, are you saying that the moderator of VBDG who banned you was one of the site admin's aliases? I wouldn't be suprised, well before the story broke, I had reasoned on one of the non-stock boards that IHUB had to be complicit in some of the stock scams rampant on the site. I got the Enemy of the People Treatment from a couple mods for that also.

DaveinHackensack said...

"Those personality tests could also be an intelligence indicator - anyone stupid enough to answer them honestly gets weeded out."

I could be wrong, but I suspect the opposite was the case. I'm thinking of one example, in particular, from a pretty involved test I took. This was for a high-end sales job at a financial services firm. One of the personality/psych questions was, "How long do you think you would work here" and it gave several possible answers. I picked the longest or second-longest number of years, since I figured that answer would sound loyal. I'm pretty sure I got that wrong though.

I generally did well on the psych parts of these tests by putting myself in an aggressive fame of mind and then using my intuition, but the aggressive, ambitious answer to that question would have been to pick a shorter tenure there. Most ambitious salesmen will begin to look elsewhere after a couple of years and will need to be placated to stay at the firm.

I'm surprised to hear that others had used the 40 yard dash analogy -- I hadn't heard it before. Re the social ineptness of high IQ types you mention, two thoughts. First, there are social inepts with low IQs too. Second, I wouldn't be surprised if groups such as Mensa are more socially inept, but these are a self-selecting group of high IQ types: the high IQ people with good social skills are probably successful enough in life that they have no need to join groups like Mensa to boost their self esteem.

Re I-Hub, yeah, the head guy -- Matt Brown -- is the one who banned me from the VBDG group. I didn't make the connection at first, as his moderator alias is just "Matt", but I asked one of the other moderators who confirmed it.

JK said...

the aggressive, ambitious answer to that question would have been to pick a shorter tenure there. Most ambitious salesmen will begin to look elsewhere after a couple of years and will need to be placated to stay at the firm.

Good point, I probably would have selected the wrong answer also. A friend of mine's wife is in the upper levels of HR at a major corporation, I will have to ask her some questions about those psych tests, e.g., how they adjust their questions knowing most people are just trying to tell them what they want to hear.

First, there are social inepts with low IQs too. Second, I wouldn't be surprised if groups such as Mensa are more socially inept, but these are a self-selecting group of high IQ types: the high IQ people with good social skills are probably successful enough in life that they have no need to join groups like Mensa to boost their self esteem.

That's somewhat true, Mensa has been called a dating service for nerds, which is not an inaccurate description. There are plenty of successful well-adjusted people in the organization, however. But in my generalization I was thinking of my AP classes instead. They were mostly comprised of recent, mostly Asian immigrants with little social life (understandable) or soft, babied mommas-boys.
I don't know how far the generalization based on my school experience extends though. Perhaps if I had gone to an Ivy, or a private high school I would have met more socially-adjusted high-IQ types. But maybe not, the lengths my peers went in order to "game" the admission system bordered on comedy. For example, they'd start a million and one pointless clubs (chess club, ping-pong club, debate club, etc -that never met!) just to paste pictures in the yearbook, to make it seem like they were involved in school life.

The most successful people I've met tend not to be the super-high IQ types, but the gregarious, assertive, intelligent-enough "B" student, who starts a company and eventually hires the high IQ types to work for him.

JK said...

Referring back the personality tests, have you ever taken a Myers-Briggs test (for yourself)? They do seem to be quite accurate. I'm an INTP. I'm just curious because judging from the blog you seem to have some INTP-ish traits.

DaveinHackensack said...

I don't think I've taken one of those, at least I don't remember taking one. What's an INTP?

I did take some sort of personality/aptitude test back in college that said I had aptitudes for business and art. I guess that wasn't anything formal like this Myers-Briggs thing.

Oh, incidentally, I forgot an example of another psych/personality question built into a job assessment test: one test had a smattering of math word problems, and among the multiple choice answers was one that said something like, "doing this problem is a waste of my time". I never checked that one.

JK said...

There are free Myers-Briggs (MBTI) tests on the internet that probably aren't as good as a professionally administered one, but if you take a couple of them and you get the same result then the results are probably accurate. Here's a chart of the sixteen basic personalities according to the theory. You can click on any of them to read about them in detail.

among the multiple choice answers was one that said something like, "doing this problem is a waste of my time". I never checked that one.

That's hilarious.