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The Lesson to Unlearn

paulgraham.com

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Re: The Lesson to Unlearn

#491

Post by sinameraji »

Love it. I wanna put this in the context of innovation in education:

IMHO, a radical innovation in education is one that can address at least two of the following flaws and failures in the current education system, at any growable scale:

–Duration and cost –Content –Delivery

If I were to satisfy a VC, I could also add a 4th bullet point called "Supply/Demand", but since I'm not writing for a VC, then I'll write what actually matters. In the case of education, that is, it's okay to ignore the existing supply and demand, and focus on the demand that must exist that doesn't yet.

Wrote a memo on these and elaborated more https://www.linkedin.com/pulse/q4-2019-what-i-see-current-st...

P.S: I think I got lucky that my mom was a teacher, so I grew up having a definition of right and wrong different from what was expected of me, and that stayed with me throughout my education. I didn't do what was asked, but what I believe was right for my growth.

Re: The Lesson to Unlearn

#492

Post by greggman2 »

halflings wrote: post #388
AlwaysBCoding wrote: post #374

Earlier quoted context omitted.

what even is cheating on an algorithm problem? looking up an answer online? asking someone in your social network to help you work through the problem? because that's what you actually do in the real world. as long as you can explain / defend your solution what does cheating even mean.

That's an idealistic way of looking at things. People would look-up solutions to that exact problem; it's very hard to come up with a unique problem that was never asked before, and questions leak pretty quickly. (especially at larger companies) The goal of a test is to evaluate whether you'd be a good employee; I agree algorithmic questions are not representative of day-to-day work, but evaluating your friend's abil…

how many things did you learn by seeing / being taught the solution and how many did you re-invent as you're basically asked to do at an interview? To give maybe a bad example, I don't know how to do a quicksort. I've written it maybe twice in my life by either being taught by a teacher or by looking it up on wikipedia. I didn't have to think of the solution on the spot. I'm not saying I can't think of solutions but still, the majority of my knowledge comes from having been taught and then using that taught knowledge over and over, not from re-invention.

Note I agree we have the same goals to hire people that can do the work not people whose friends can do the work but I'm not convinced that the typical interview puzzles (find the longest segment of an array that contain 3 values) has anything to do with actual work skills. Maybe it would be better with more typical tasks? If the person claims to be back end engineer ask them to write a query to select all people between the ages of 30 and 35 in Nebraska? Maybe if they are front end ask them to implement a select/option UI?

Re: The Lesson to Unlearn

#493

Post by SamReidHughes »

kick wrote: post #297
coffeemug wrote: post #276

Earlier quoted context omitted.

No, you cannot. IQ is highly correlated with wealth and is also highly heritable. So in all likelihood what you've observed is that smart kids win academic competitions, and also happen to be from rich families. If you take a bunch of kids with an IQ of 100 (or 115, or even 130) and put them into private schools they'll do a little better but they won't be winning any academic competitions.

The available data disagrees with you on this: https://doi.org/10.1126/science.1238041

Some information about the flaws with that data:

https://www.researchgate.net/publication/259207757_Comment_o...

Re: The Lesson to Unlearn

#494

Post by isidor3 »

taeric wrote: post #342
isidor3 wrote: post #317

Earlier quoted context omitted.

Heavier things do gain kinetic energy faster when falling, it's easy enough to confuse "being hard to stop" with "moving fast." Intuitively, the heavier object has "more" of something but in casual conversation "kinetic energy" isn't a common or familiar term. If you haven't studied enough physics to reach for that concept, I'm not surprised a lot of people just settle on "faster" when attempting to describe it.

Yeah, and we have words for that. Momentum, is a good one. I should clarify the last time I had this conversation, I'm talking about 40+ year olds building bikes. They were thinking a heavier bike would accelerate faster down a hill. That just is not how that works.

It actually is though! The force due to air resistance is the primary thing slowing down the bike and rider, and the force, which doesn't change with mass, slows down a heavier bike less, and so a heavy bike will be rolling faster than a lighter one at the bottom of a hill, all other things being equal.

Re: The Lesson to Unlearn

#495

Post by senderista »

dominotw wrote: post #472
iudqnolq wrote: post #463

Earlier quoted context omitted.

Are you proposing brute forcing it? Depending on requirements that might be fine, but I doubt FB would like that kind of solution. If they did, they'd have a different kind of question.

1st for loop with first word with charecter counts map and second for loop subtracting counts from frist map. See whats remaining in the end, either a map with 1 char left or 1 char left in second. so O(m + n). abc , adc a - 1 b - 1 c - 1 after second word loop b - 1, d

That only works up to permutations.

Re: The Lesson to Unlearn

#496

Post by SamReidHughes »

kick wrote: post #269
coffeemug wrote: post #250

Earlier quoted context omitted.

Don't know about Page and Brin, but according to the Netflix documentary Gates won state-level math Olympiad at a level three grades higher than his own. So he wasn't a modal child. You can't draw any conclusions from that about education at scale.

You actually can: if he had a better level of education than everyone else, why wouldn't he do better than people taking traditional educational paths? As someone who participated in many academic competitions as a child, the winners were consistently weighted 9:1 private:public.

Let's see: https://www.maa.org/sites/default/files/pdf/AMC/usamo/2019/2...

On the first page, the breakdown is 23 kids from public schools, 7 kids from private schools, 4 kids listing some sort of math circle / whatever Arateem is, 5 kids listing universities (home schooled/taking uni courses? No idea). Possibly a few of the private school kids are on scholarship. The 7 kids go to 4 schools.

Re: The Lesson to Unlearn

#497

Post by jhatemyjob »

Paul Graham is one of the most powerful people on the on the planet. Of course he sees "hacking bad tests" (aka politics) as something that will become obsolete. He has the privilege of ejecting from any political situation he finds unpleasant.

Meanwhile, the other 7B population with substantially less power, we have to deal with each other. Politics are, and always will be, a thing. As long as people exist.

Re: The Lesson to Unlearn

#498

Post by taeric »

isidor3 wrote: post #494
taeric wrote: post #342

Earlier quoted context omitted.

Yeah, and we have words for that. Momentum, is a good one. I should clarify the last time I had this conversation, I'm talking about 40+ year olds building bikes. They were thinking a heavier bike would accelerate faster down a hill. That just is not how that works.

It actually is though! The force due to air resistance is the primary thing slowing down the bike and rider, and the force, which doesn't change with mass, slows down a heavier bike less, and so a heavy bike will be rolling faster than a lighter one at the bottom of a hill, all other things being equal.

Right, you can hit a higher velocity. You will not get extra acceleration. That is my entire point.

That is to say, the force from the air does not actively slow you down. It prevents you from speeding up, after a point. (Aerodynamics are, of course, more complicated. But this general model is pretty solid.)

Such that if I want to accelerate faster down the hill, I have to pedal to cause that to happen. Or add a motor.

Re: The Lesson to Unlearn

#499

Post by cellularmitosis »

anon9001 wrote: post #392
dominotw wrote: post #309

Earlier quoted context omitted.

Haha here is the email i have from my facebook interview thats coming up. "Your initial Facebook interview is coming up and we want you to ace it! Here are some tips and resources so you know what to expect and can prepare adequately. Preparing is key. Our initial interview determines whether to continue with a full series of onsite interviews. This initial interview is primarily a coding interview that will take pla…

> Write a function to return if two words are exactly "one edit" away, where an edit is: Inserting one character anywhere in the word (including at the beginning and end) Removing one character Replacing exactly one character I've been writing code my entire life, and I've been employed as a software developer for longer than I'd care to admit. I don't have a quick answer to that problem. I know there's an algorithm…

Many of these sorts of problems seem intimidating at first, but if you’ve had any training / exposure to implementing recursive solutions (i.e. a bit of SICP), the solutions come much easier because you are trained to think in terms of “what is the tiniest amount of work I can do to advance the problem by one step?”

In this case, all we need at each step is to look at one character plus one lookahead character from each string. We’ll call them a and b for string 1 and c and d for string 2.

If a and c are equal, advance.

If a and d are equal, delete c and advance.

If b and c are equal, delete a and advance.

If b and d are equal, change one of a or c so they match, then advance.

Once you use up an edit, the algo changes to “a and c must match” for the rest of the string.

Edit: terminate the algo when one of a or c is a NULL char. If they are both NULL, the string passes. If only one is NULL, then your one edit allowance was not enough to make the strings equal.

Also, rather than “deleting” a char, it is sufficient to simply advance that pointer an extra step.

Re: The Lesson to Unlearn

#500

Post by ZguideZ »

Tsunebaro Makiguchi, an early 20th century Japanese educator, was striving towards deconstruction of rote education but his work was disrupted by authorities who worried that his educational revolution would disrupt orderly Japanese society. Careful, PG, you might be rocking the boat too much with this. ;)
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