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Electron band structure in germanium, my ass (2001)

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Re: Electron band structure in germanium, my ass (2001)

#291

Earlier quoted context omitted.

> Should they expect a good performance evaluation? They should expect that particular incident to not affect their performance evaluation, since it was very much not their fault. In your hypothetical scenario, your hypothetical junior engineer went to the senior engineer repeatedly for advice, and the senior engineer did not do their job properly: The lab tech was unhelpful, insisting that it must be something with…

> They should expect that particular incident to not affect their performance evaluation, since it was very much not their fault. What do you mean not their fault? I've seen wrong parts delivered by suppliers, so yes responsibility of an engineer who puts together a circuit is definitely checking that the parts are correct. > In your hypothetical scenario, your hypothetical junior engineer went to the senior engineer…

> What do you mean not their fault? I've seen wrong parts delivered by suppliers, so yes responsibility of an engineer who puts together a circuit is definitely checking that the parts are correct.

Let's not move the goal posts, please. If you're going to use a hypothetical situation as an analogy, make sure it's actually analogous. Yes, an engineer who puts together a circuit has that responsibility, because they're an engineer. They went through the required training that makes them an engineer and not just an engineering student.

> I find it hard to believe that the lab tech said it could never be the parts, considering how those things are handled in student labs, small parts break all the time.

And therein lies the problem. You "find it hard to believe" that the lab tech could have been that unhelpful, just like the lab tech found it hard to believe that the student wasn't doing something wrong. Both you and the lab tech are behaving in a way that is inappropriate for a senior mentoring a junior.

In my experience mentoring others, the first assumption should not be that the person you're mentoring simply didn't do enough and that they should try to do better. Yes, that might end up being the case, but most of the time there's also something else that could have been done better. Maybe the documentation is not clear enough, maybe the process didn't help catch the mistake, maybe the expectations I set weren't clear enough, maybe I didn't communicate well enough.

"Go check your work again" is rarely helpful, even in the extremely rare cases where that's the only thing that needed to be done and no other improvements exist. If you're really convinced that they merely need to check their work again, guide them to it.

That's why they are junior and you are senior, because they need more guidance than you do. They will not develop the necessary insights and instincts without that guidance.

> I've seen the other side of the equation as well, when things don't work students often just throw their hands up and say "it doesn't work" without any of their own troubleshooting expecting the tutor/lab tech/professor to do the troubleshooting for them (quite literally, can you check that we wired everything correctly...)

And in turn, you're arguing that the mentor should merely throw their hands up and say "go check your work yourself". Again, even that can be said differently: "Can you explain what you have checked so far and how you've checked it?"

> Simply saying "it wasn't my fault because I had a wrong part" shouldn't just give you an A.

You are drawing a lot of your own conclusions from what hasn't been said. In this comment thread, you have repeatedly and consistently shown bias through your assumptions. Yes, what you're saying could have been the case, but I see no evidence of it and no reason to simply assume it without at least inquiring about it.

Re: Electron band structure in germanium, my ass (2001)

#292
post #99

Earlier quoted context omitted.

This is, more or less, exactly what happened when I took Electronics I in college. The course was structured in such a way that you could not move on to the next lab assignment until you completed the one before it. You could complete the lab assignments at your own pace. If you failed the lab, you failed the class, regardless of your grade. The second or third lab had us characterize the response of a transistor in…

What I don't understand is why it took you 8 weeks to distinguish a timer from a transistor. That doesn't make your professor's reaction alright, I just find it puzzling.

relatively cheap lesson in the importance of knowing your hardware.

Re: Electron band structure in germanium, my ass (2001)

#293
post #124

Earlier quoted context omitted.

Same package. 555 is typically a DIP-8, transistor packages are available in the same. So you would have to examine the cryptic markings and compare them with the other students, and that’s only if you suspected some fuckup on the part of the knowledgeable people.

But that's the thing that both students and often the teachers forget. We don't run labs to go smoothly, we run labs because you'll have to troubleshoot. There is no learning experience in a lab that works without issues, in fact IMO if lab instructions are of the step by step type, they should always have some deliberate errors in it to get students to troubleshoot. To play devil's advocate, just imagine the previou…

While it's ridiculous to expect a student to have the skills of a professional, even a student needs to develop assertive skills to demand a replacement part. This is a basic skill for debugging hardware problems: see if problem manifests on more than one unit. Here it would be demanding another chip to try, early-on. Chips can be marked correctly but damaged or defective.

Re: Electron band structure in germanium, my ass (2001)

#294
post #27

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopw…

>The lesson is taught early and often. It often sort of baffles me when other people are baffled at how often this happens in science, Math and some sciences have the aura of definitive right and wrong, so even though by college everyone knows the expression "give the answer the teacher wants to hear", they just think in those subjects the teacher has access to absolute answers. The primary thing taught by our school…

I studied Engineering rather that physics. In our lab reports we were expected to include a discussion of the results and the experimental method. It was basically expected that the report should include associated commentary around potential sources of error and modifications to improve the experimental accuracy.

I don't recall ever being marked down for failing to obtain the "correct" result the impression I came away with was so long as you were thorough in your discussion and analysis the exact result was less important.

I can remember my second year thermodynamics class had a fairly complicated lab which involved taking measurements from inflow and outflow of various heat exchangers in a variety of configurations (Counter flow, Cross flow etc) then computing the efficiency of each configuration. I recall getting into minutiae in the report about assumed friction factors and suggested methods to asses the smoothness of the pvc pipes etc. to improve the accuracy of calculations etc.

Re: Electron band structure in germanium, my ass (2001)

#295

Earlier quoted context omitted.

I was in honors freshman chemistry at university. Tough class, all homework (lots of it) graded rigorously, but only the midterm and final counted toward the course grade. So if you wanted an A you had to get an A on both exams. After midterm, during every other lecture at least, the professor would sound a refrain: “An orbital is not a house! An electron does not live in a house!” Final exam had a small number of co…

I agree this seems overly principled to me. I recall a DSP class where there was an exam with a question like (not exactly this): > What does the following code print? > `printf("Hello, world!");` If you responded with: > Hello, world! ...which - of course - the whole class did, you got the question wrong. If you responded with: > "Hello, world!" ...which is actually not what that would print, you got the question ri…

The kind of prof who never coded a useful program in his life.

Re: Electron band structure in germanium, my ass (2001)

#296
post #27

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopw…

I'm certainly not going to defend your teacher or your experience, especially at the high school level. That's too soon. And I also remember being indignant for a similar experience in analytical chemistry.

But... there's a point in one's development as a science student, where science becomes more nuanced than "doing your best and honestly reporting what you observe." Those things will always be there of course. But in an experimental science, doing an experiment and getting accurate results is a vital skill, or you'll never make progress.

Naturally you have no standard for checking a measurement whose result is truly unknown, but you can insert the equivalent of breakpoints where you make sure that the same data do reproduce known results. Ironically for the discussion here, those are called "gravity tests." Students need to know at some point if they're going to like the experimental side of science. Getting things right is part of it. Some people don't belong in the lab.

I happen to be stuck at the "gravity test" level in my day job. My experiment produced a calibration that's reproducible, and that I could use, but it doesn't make sense. I'm not going to move forward until it does.

The problem with a lot of teaching is that the purpose of the lesson is never explained, and the nuanced view is never spelled out.

Re: Electron band structure in germanium, my ass (2001)

#297
post #232

Earlier quoted context omitted.

My physics professor told us once about a lab he had to do when he was a student himself, about measuring the adiabatic gas constant of air. The workload at that point was immense, so lots of students would just write a report and give the textbook answer—and be marked wrong. It turned out the TA had sabotaged the experiment by putting alcohol in the bottom of the (dark glass) measurement bottle, so the measurement w…

The trouble with these kinds of games is that they put the more diligent students at a disadvantage. For example, someone might compare their experimental result against the textbook constant, realise it's wrong, and spend much more time trying to identify their "mistake", not realising they've been sabotaged. This puts further pressure on their other work. One cannot argue that this is fair on the basis that it's th…

Not only that, but an appropriately diligent student might notice with their eyeballs or nose that their bottle contained alcohol, and clean/dry it before performing the experiment.

Re: Electron band structure in germanium, my ass (2001)

#298
post #274
post #143

Earlier quoted context omitted.

You can square that circle by announcing at the beginning of the course that there is going to be some assignment like that, but I'm not telling you which, because the real world doesn't. I do agree this is a good point; trust is not something that should be simply squandered. Nevertheless, this is still a lesson that needs to be taught and so often students make it to the end without a single teacher that did.

This is ambitious. I once had a college class where the students were very upset because I decided to change the number of in-class quizzes from 5 to 4 a few weeks into the course. (The quizzes made up 10% of the overall grade.) Students hate it when you do anything even remotely weird or unexpected with assessments. Telling them that there is going to be a mystery trick assessment will just make them anxious and gru…

Right but doing it without saying anything is much worse.

Re: Electron band structure in germanium, my ass (2001)

#299

hahaa, I love it! That's right there is engineering and true work and dedication. Can hear the frustration and it's 100% warranted. I wish universities were better equipped for what you pay. Where is all that money going anyways? Leaking like free electrons?

The 2023 education and general fund budget for Penn State allocated 5.7% to equipment and maintenance and repairs of approx $2.5 billion in use. I assume that would include thing other than just lab equipment. Overwhelmingly, most education fund use goes to salary, benefits and student aid (~$2 billion, 81%). Interestingly the amount of money raised by tuition and fees almost exactly matches the amount spent on salar…

Wow, you went down the rabbit-hole, much appreciated! Do I understand correctly, that your analysis boils down to the money is indeed being pocketed rather than used for equipment or improving anything at all at the university?

Re: Electron band structure in germanium, my ass (2001)

#300

Earlier quoted context omitted.

If you happen to have a good ruler (again, 1720s... Those also cost money or time to make). A ruler and a T-square would work. But still, it's more complicated and requires a lot more bench to secure things in place at angles than folding a piece of string in half.

Well... Yeah. It costs money and/or time to make things. That's as much true now as it was back then, but I don't think a ruler would have been particularly difficult to make, even with 18th century technology.

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