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Algorithms, by Jeff Erickson

jeffe.cs.illinois.edu

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Re: Algorithms, by Jeff Erickson

#221

Post by d4rti »

skizm wrote: post #219

What the heck is the trivial one liner to check who will win a chess game given both players play perfect?

I can only come up with a recursive algorithm which depends on a PerfectPlay(state, player) like so:

    WinnerWithPerfectPlay(state,currentPlayer):
      if Winner(state)
        return Winner(state)
      else
        nextPlayer
Which doesn't allow for stalemate moves.

Re: Algorithms, by Jeff Erickson

#222

Post by DonaldPShimoda »

emme wrote: post #211
DonaldPShimoda wrote: post #203

Earlier quoted context omitted.

I've tried a few approaches to explaining recursion ("just assume that it works", "trust yourself", "turn off your brain" (the latter of which is from Will Byrd)), but I like "Recursion Fairy" an awful lot. Might have to try that next time.

We designed a small tool to bring the fairy metaphor even to lower secondary school students. I actually believe it is a very promising approach. "Nothing to fear but fear itself: introducing recursion in lower secondary schools" https://aladdin.di.unimi.it/materiali/pubb/2017_latice.pdf

That looks super interesting! I'll take a deeper look when I get the chance. Thanks for sharing!

Re: Algorithms, by Jeff Erickson

#223

Post by jimhefferon »

mesaframe wrote: post #196
jimhefferon wrote: post #51

Earlier quoted context omitted.

Perhaps you might, when you get a chance, email him a brief note to tell him that. That'll make a person's day.

You know what, your book on linear algebra is really great too. I tried to understand LA from too many books but your book was the one which made sense for me.

:-) Thank you.

Re: Algorithms, by Jeff Erickson

#224

Post by specialist »

jefferickson wrote: post #186
specialist wrote: post #158

Earlier quoted context omitted.

Idea from common job interviewing process: Make the unit tests public. Or useable interactively online. I know it'd be a lot more work. If you had a repo for unit tests, I'd contribute.

WHAT unit tests? This is not a book about programming. The solutions are not code. None of the homework in my algorithms classes CAN be auto-graded.

Oh. Serves me right for not peeking at your book first. My bad.

Re: Algorithms, by Jeff Erickson

#225

Post by SilasX »

solveit wrote: post #179
nichochar wrote: post #170

Earlier quoted context omitted.

I think you're running under the assumption that all students making the request are doing it for the right reasons. I could be wrong, but my intuition goes the other way and I'm assuming most students do it to get a better grade, not learn more.

Yeah no, you don't get to say students should care more about learning than grades when jobs, opportunities, and scholarships given by the very university that claims learning is more important are riding on grades. It is the professor's responsibility to grade accurately, and honestly if there is so much inconsistency in grading that there's a significant probability that the student will lose marks despite having p…

Exactly. It's ridiculous that teachers are fine with such inconsistent grading on something they (and their graders) are supposed to be experts at -- let alone that they take such joy in leveraging such unhelpful inconsistency against students who objected to them propagating falsehoods!

It reminds me of those "drunk driving costs you $15k" ads, where most of that comes from the expense of navigating the court system (bail, attorney's fees), and the state is somehow proud of this fact.

Re: Algorithms, by Jeff Erickson

#226

Post by jefferickson »

alfrapi wrote: post #102
primitivesuave wrote: post #66

Jeff Erickson was my algorithms professor in 2012. He exemplifies the articulate, passionate educator that I wish I had for my other CS subjects. I recognize many of these notes having read them many times in preparation for quite difficult exams - a fun anecdote shared among people who've taken the class is the 25% credit given on any exam question just for writing "I don't know", effectively a reward for acknowledg…

I think the rule was you had to attempt at least one question (couldn't say "I don't know" for the whole exam). Am I remembering that correctly?

No, I've had several students answer "I don't know" to every question on the final exam. (About one every two or three years.) Without exception, they got a 25% on the exam and an F in the class.

Other theory instructors at Illinois do put limits on their IDK policy, like "at most 10% of the total points", or "for at most one question", or "not in my class". So far I've stuck to my guns.

Re: Algorithms, by Jeff Erickson

#227

Post by atombender »

jefferickson wrote: post #204
webmaven wrote: post #35

Great resource, though I wish it was available as an EPUB (or MOBI, or AZW3).

You can get an EPUB and MOBI versions from the Internet Archive (auto-converted from my uploaded pdf), but I can't vouch for its quality. All the fonts are baked into the PDF, so it should be readable anywhere; if it isn't, please submit a bug report! But if you're looking for a format that lets you reflow the text, by changing the margins or font or text size, you're out of luck. The only way to write something like…

I don't know what you use to typeset the book, as I can't find any source files, but isn't LaTeX really good at this?

I'm not sure what makes it hard to reflow. The text seems to be mostly paragraphs with figures, inline formulas and footnotes; pretty basic stuff, no?

(O'Reilly's books were famously typeset with Troff/Groff for many years, though I don't know how painful that was or how advanced their typesetting needs were.)

All I know is that I'd love a version that worked on smaller devices. I tried the Kindle version reformatted by archive.org, but it has lost most of the formatting, making it almost completely unreadable.

I'd especially like an HTML version of the book that was fully hyperlinked, with zoomable vector figures, footnotes hidden away in popups, etc.

Re: Algorithms, by Jeff Erickson

#228

Post by satsuma »

jefferickson wrote: post #86
_underflow_ wrote: post #3

> Please do not ask me for solutions to the exercises. Even if you are [an] instructor, I will say no. That's kind of a bummer. I like to be able to check my answers when teaching myself things. Am I somehow alone in that?

Hi, I'm the author. I'm honestly seriously torn about this. There is a serious tension between pedagogical needs of students in formal classrooms and the pedagogical needs of self-learners. I've chosen to aim for the former. Yes, I know it's a bummer. (From experience) providing solutions interferes with the learning process of my own students at Illinois. I have to change up homeworks and exam questions every semest…

thank you for the reference material! i'm a student at central michigan right now and will be heading into my intro. to algorithms class this upcoming semester. i'll be sure to use it to supplement (and not pester you for free answers)

from what i see elsewhere in this thread, you've got quite a good reputation around illinois. i recently lost a favorite professor of my own mid-semester last year, and it made me realize just how much a good instructor means to people. so thank you for being that for students!

Re: Algorithms, by Jeff Erickson

#229

Post by emme »

DonaldPShimoda wrote: post #222
emme wrote: post #211

Earlier quoted context omitted.

We designed a small tool to bring the fairy metaphor even to lower secondary school students. I actually believe it is a very promising approach. "Nothing to fear but fear itself: introducing recursion in lower secondary schools" https://aladdin.di.unimi.it/materiali/pubb/2017_latice.pdf

That looks super interesting! I'll take a deeper look when I get the chance. Thanks for sharing!

You're welcome!

Re: Algorithms, by Jeff Erickson

#230

Post by emme »

ff_ wrote: post #213
emme wrote: post #211

Earlier quoted context omitted.

We designed a small tool to bring the fairy metaphor even to lower secondary school students. I actually believe it is a very promising approach. "Nothing to fear but fear itself: introducing recursion in lower secondary schools" https://aladdin.di.unimi.it/materiali/pubb/2017_latice.pdf

Super interesting! Do you happen to have an Italian translation/version of the paper?

No, I'm sorry... It was thought in Italian... but written only (more or less) in English :-)

But the supporting tool is actually in Italian:

https://aladdin.di.unimi.it/sw/fatine/

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