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Why Your Professors Suck

zacharyernst.blogspot.com

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Re: Why Your Professors Suck

#51

Post by kevinxucs »

rmrfrmrf wrote: post #36
Blahah wrote: post #25

> Good student: "When will the midterm be?" > Me: "Why do you care?" > Good student: "Um... I'd like to be able to plan when I > should study for it." > Me: "Oh, okay. I don't know when it's going to be." > Good student: "Um... Okay. What's it going to cover?" > Me: "I'm not sure, but it'll be really great!" > Good student: "That's good, I guess. Can you be more specific?" > Me: "Not really. But why do you care?" Wow…

I think you're taking that conversation the wrong way. When I saw the exchange, I sympathized with the author immediately because I've been in this situation many times . It's very distracting when a professor is giving an in-depth lecture, then suddenly, the "good student" pops their face up from their daily planner and raises their hand in the most conspicuous way possible. "Oh, man," I think, "the professor was on…

Well, our professor seems to adept to this kind of students very well - he will tell us whether it will be on the exam immediately after he finished a point.

Re: Why Your Professors Suck

#52

Post by yummyfajitas »

eli_gottlieb wrote: post #50
yummyfajitas wrote: post #42

Earlier quoted context omitted.

It's not even necessary for the topics to be politically controversial (by which I mean Democrats and Republicans have opinions on it) for this effect to occur. You can get the same filtering effect purely via internal pressures. As examples, consider the Copenhagen consensus in foundations of quantum mechanics or the (currently being overturned, thanks to machine learning) Frequentist consensus in statistics.

About the statistics thing: I thought that Frequentism and Bayesianism were two separate frameworks to use in two separate contexts? Basically, I thought that you used Frequentism when you could do a definite experiment that yields an exhaustive probability distribution (like rolling a die to see how often it yields each number), while you use Bayesianism to evaluate accumulations of evidence about a distribution you…

That's not correct. Frequentists view the world as an experiment measuring a set of unknown parameters describing a probability distribution. These parameters are fixed, and cannot be described probabilistically.

In contrast, Bayesians use probability to represent uncertainty.

I.e., to a Frequentist, it doesn't even make sense to ask the question "what is the probability that the coin is rigged", whereas the Bayesian would come up with a probability distribution for the probability of the coin coming up heads.

Re: Why Your Professors Suck

#53

Post by glenra »

anon1385 wrote: post #23
snitko wrote: post #16

The structural problem he mentioned at the end is this: students are not customers. Had they been customers, who could instantly stop paying this professor because they think he's boring and doesn't deliver, you'd see a completely different picture. It wouldn't be about grades and diplomas anymore. It would be about acquiring knowledge and skills that students can later apply. If they decide this professor cannot tea…

The other side of students being customers is that they will see a passing grade as something they have paid for and should receive, not something based on merit. If you paid a lot of money for a course but didn't get a good grade are you more likely to blame yourself or blame the teacher? More likely to give good feedback to a lecturer that gave an A because the course was easy or to a lecturer that gave a C for a v…

That seems pretty simple to solve - just decouple the courses from the grading process. Let the teacher specialize in teaching and let some other firm that specializes in testing rate/certify your resulting competence or lack thereof in the subject.

Re: Why Your Professors Suck

#54

Post by dnautics »

yummyfajitas wrote: post #42
dnautics wrote: post #14

Earlier quoted context omitted.

As a practicing (bio)chemist, I am usually somewhat cynical about philosophy professors, but what this guy says is spot on. Perhaps this is a self-serving agreement, since I was definitely one of these "good bad students". In my experience, yes, including your minor clarification on the word 'good', the full description applies equally to chemistry as philosophy (presumably). But then that makes one wonder: Why are w…

It's not even necessary for the topics to be politically controversial (by which I mean Democrats and Republicans have opinions on it) for this effect to occur. You can get the same filtering effect purely via internal pressures. As examples, consider the Copenhagen consensus in foundations of quantum mechanics or the (currently being overturned, thanks to machine learning) Frequentist consensus in statistics.

That's why i said "cancer research" at the end. But the additional problem is that if it's politically controversial, by and large most research is paid for at the leisure of politicians, so you wind up with another layer of circular pressure.

Re: Why Your Professors Suck

#55

Post by beambot »

nagrom wrote: post #7
beambot wrote: post #4

Definitely not an engineering prof. Top university professors (ie. R1 schools) are primarily judged on their research , not their teaching . If your professors "suck" it's because they're spending all of their time on the things that matter to their careers: grant writing and publications. And students (good or bad) care about exam times because of... procrastination. The "bad" students (of the goof-off variety) don'…

The top professors tend not be judged on their research, in my experience. They're judged on their publications. I, personally, know many 'top' professors that have enormous publication lists that come from being the guy who supplied the money via a grant application. From their publication list - which is what 'proves' their research excellence, you would be forgiven for thinking that they were savants. But they're…

Publications (or more generally, H-Index) are used as a proxy for research by administrators that cannot possibly judge the merits of the research itself. During the tenure process, administrators use other signals too: recommendation letters from peers, grants, "service", graduated students and their placements, etc.

When your work is only relevant or approachable to less than a dozen people on the planet, how can you expect a dean to judge it? They can't. So they use (often poor) proxies.

Re: Why Your Professors Suck

#56

Post by dnautics »

yummyfajitas wrote: post #52
eli_gottlieb wrote: post #50

Earlier quoted context omitted.

About the statistics thing: I thought that Frequentism and Bayesianism were two separate frameworks to use in two separate contexts? Basically, I thought that you used Frequentism when you could do a definite experiment that yields an exhaustive probability distribution (like rolling a die to see how often it yields each number), while you use Bayesianism to evaluate accumulations of evidence about a distribution you…

That's not correct. Frequentists view the world as an experiment measuring a set of unknown parameters describing a probability distribution. These parameters are fixed, and cannot be described probabilistically. In contrast, Bayesians use probability to represent uncertainty. I.e., to a Frequentist, it doesn't even make sense to ask the question "what is the probability that the coin is rigged", whereas the Bayesian…

Largely, though it's a matter of terminology[0]. I doubt that any but the most dogmatic frequentist would say there isn't something to the notion behind the question you're asking "what do you think is the chance the coin is rigged", but rather that it should not be conflated (by using the term "probability") with the notion of a situation where something can be repeated and measured - or at least one that sufficiently approximates that situation.

[0] I find that battles over terminology can be the harshest and most recriminating minefields among the intelligent.

Re: Why Your Professors Suck

#57

Post by eli_gottlieb »

dnautics wrote: post #56
yummyfajitas wrote: post #52

Earlier quoted context omitted.

That's not correct. Frequentists view the world as an experiment measuring a set of unknown parameters describing a probability distribution. These parameters are fixed, and cannot be described probabilistically. In contrast, Bayesians use probability to represent uncertainty. I.e., to a Frequentist, it doesn't even make sense to ask the question "what is the probability that the coin is rigged", whereas the Bayesian…

Largely, though it's a matter of terminology[0]. I doubt that any but the most dogmatic frequentist would say there isn't something to the notion behind the question you're asking "what do you think is the chance the coin is rigged", but rather that it should not be conflated (by using the term "probability") with the notion of a situation where something can be repeated and measured - or at least one that sufficient…

Ok, so frequentists believe P(x) for some event x is the limit of the fraction of trials in which x happens, as we increase the number of trials to infinity.

Whereas Bayesians believe P(x) is odds at which they would gamble, so to speak, that a particular proposition x is true.

Is that it?

Re: Why Your Professors Suck

#58

Post by yummyfajitas »

eli_gottlieb wrote: post #57
dnautics wrote: post #56

Earlier quoted context omitted.

Largely, though it's a matter of terminology[0]. I doubt that any but the most dogmatic frequentist would say there isn't something to the notion behind the question you're asking "what do you think is the chance the coin is rigged", but rather that it should not be conflated (by using the term "probability") with the notion of a situation where something can be repeated and measured - or at least one that sufficient…

Ok, so frequentists believe P(x) for some event x is the limit of the fraction of trials in which x happens, as we increase the number of trials to infinity. Whereas Bayesians believe P(x) is odds at which they would gamble, so to speak, that a particular proposition x is true. Is that it?

It's deeper than that. The difference in views influences everything you compute. For example, Frequentists compute p-values, which is P(reject null hypothesis | null hypothesis is true) [1].

In contrast, Bayesians compute P(null hypothesis is false | prior knowledge).

Similarly, Frequentists compute confidence intervals (say at 5%), which is an interval that represents the set of null hypothesis you can't reject with a 5% p-value cutoff. In contrast, Bayesians compute credible intervals, which represent a region having a 95% probability of containing the true value.

Personally, I'm solidly in the Bayesian camp simply because I can actually understand it. To take an example, consider Bem's "Feeling the Future" paper [2] which suggests that psychic powers exist. From a Bayesian perspective, I understand exactly how to interpret this - my prior suggests psychic powers are unlikely, and my posterior after reading Bem's paper is only a little different from my prior. I don't know how to interpret his paper from a Frequentist perspective.

[1] http://www.bayesianwitch.com/blog/2013/godexplainspvalues.ht...

[2] http://www.dbem.ws/FeelingFuture.pdf For background, his statistical methods were fairly good, and more or less the standard of psychology research. If you reject his paper on methodological grounds, you need to reject almost everything.

Re: Why Your Professors Suck

#59

Post by snitko »

glenra wrote: post #53
anon1385 wrote: post #23

Earlier quoted context omitted.

The other side of students being customers is that they will see a passing grade as something they have paid for and should receive, not something based on merit. If you paid a lot of money for a course but didn't get a good grade are you more likely to blame yourself or blame the teacher? More likely to give good feedback to a lecturer that gave an A because the course was easy or to a lecturer that gave a C for a v…

That seems pretty simple to solve - just decouple the courses from the grading process. Let the teacher specialize in teaching and let some other firm that specializes in testing rate/certify your resulting competence or lack thereof in the subject.

That is a very good idea, I don't understand where the downvotes come from.
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