Computer Science

12:17 AM

Can someone please tell me the reasoning behind "therefore" in the second line of the proof here: en.wikipedia.org/wiki/…

Gilles

12:30 AM

@WuschelbeutelKartoffelhuhn pidgeonhole principle?

Wuschelbeutel Kartoffelhuhn

got it thanks

vzn

1:43 AM

6

Q: What should be included in a freshman 'Mathematics for computer programmers' course?

Many universities are changing up the way that they teach math service courses. 1-3 semesters of calculus and maybe a course in linear algebra are often included in majors (such as computer science) that will not use the majority of the material. However, these courses are often justified by say...

vzn

5:10 AM

0

Q: list of cool research project topics

over 2yrs have noticed that ppl asking about what to work on for research projects (undergrad, grad, phd) is a common query around stackexchange. these questions are almost invariably quickly closed on main sites. this seems a bit of a shame to me. for most of us, we are all in CS for personal re...

discussion

....

mass meta split!

246

Q: Operation 'Split, All The Metas!' Shall Commence On April 16, 2014

Update 2014-04-17 04:47 UTC: Stable, with some odds and ends to clean up The main MSO/MSE sites are stable, but there are plenty of corners left to sweep. For details, see: The Status Of The Split Not all of them mind you, just Meta Stack Overflow into Meta Stack Exchange. I'll have yo...

discussion featured mso-mse-split

Gilles

7:16 AM

Ok, you insist on using silly abbreviations, not capitalizing words and generally breaking the conventions of the English language. Fine. But do it in your blog or in your volumes of poetry. We are here to communicate. That means using our common language, English. Making mistakes is not a problem, but when you deliberately write in order to be hard to read, I'm not going to spend time trying to decipher what you wrote. If anyone cares to edit this question and translate it into proper English, and it turns out to be on-topic here, I'm all for reopening it. — Gilles ♦ 24 secs ago

@vzn I've told you before: if you want to communicate with others, don't speak in a lingo of your own.

Wandering Logic

11:22 AM

Is there some way of running queries over stackexchange data? I'm interested in quantifying overlap between tags on various sites (cs and scicomp, dsp and electronics and cv, ...).

This is for a meta.se question I am composing requesting the ability to cross-post a question to several sites simultaneously.

Gilles

12:22 PM

@WanderingLogic yes: through the API, or through the data explorer. Which one to use depends on what you want to do. Neither method makes it easy to do queries overlapping all sites, but queries overlapping O(1) sites can be done

@WanderingLogic this has been proposed many times and shot down, make sure to read the existing work before proposing something

Wandering Logic

12:56 PM

@Gilles thanks!

@Gilles I have been reading some related meta posts. That's why I need to collect data.

SE staff responses are invariably along the lines of "there is not possibly any overlap between sites."

Realz Slaw

peerproduction.net

@vzn ^

vzn

3:25 PM

gilles re kneejerk closing the meta question, there is nothing unclear about it

2 hours ago, by Wandering Logic

SE staff responses are invariably along the lines of "there is not possibly any overlap between sites."

lol!

ridiculous

wanderinglogic, crossposting is an interesting idea but would bet $x that it wouldnt be implemented in a million years

the se architecture is pretty mature & afaict major chgs havent been made in years

eg migration is an older mechanism that hasnt chged much.

Realz, interesting! thx for link

did you see my recent blog on games? cited you

Wandering Logic

4:51 PM

@vzn: meta.stackexchange.com/a/64069/218898

"Each site is focused on a specific topic area. If you have a question you feel is too ambiguous, either re-think the question carefully, or [get it migrated].

99.99% of questions people have labeled as being applicable cross-site have been proven to be valid on a single site if written properly and thought through. SE is not a wild west for questions; a question needs to be worked on to be worthy, and if worthy, it will target a specific audience."

=D

The problem I'm really concerned about specifically is the rapid proliferation of applied computer science betas either already going or being proposed.

For a lot of these there will be substantial overlap between the proposed new site and some combination of cs and so (for the programming questions)

It's a reasonable argument that it is difficult to build a cohesive community when your question base needs to be divided between two existing sites.

So you get proposals for operating systems

and compilers

and programming languages

and artificial intelligence

and artificial intelligence!

oh yeah: and artificial intelligence

gotta go, but the machine intelligence community keeps trying

the scicomp community and dsp community and ee communities all have overlap with us

and there were several mostly overlapping "computer engineering" type proposals a while back.

*********************

so the real question is: how can we allow subcommunities to form effectively?

Area51 + no crossposting clearly ain't it

vzn

5:16 PM

hi wanderinglogic.

another issue is that some sites are long in beta and are not ever reaching "critical mass" eg this one. so why are there new cs-related proposals in area51?

know what that suggests to me... that the existing sites are too inflexible/conservative/restrictive in their charters.

yes stuff like AI doesnt fit too well in existing sites (despite a tag for it), was disappointed not to see it succeed in area51.

am starting to wonder if the best idea is some kind of capability of reorg based on tags, where a site could accumulate tags but then say "lets push these tags somewhere else"... there is some discussion of that with the new stackexchange meta site. [gilles himself proposed that in a meta response]

imagine if all the ai tags across existing sites suddenly got re-org'd into a new site... hmmmm

yes dont really like the area51 mechanisms myself much, its very difficult to build communities there... :(

maybe purposely so.

area51 is yet another se ghetto-like area.

Wandering Logic

@vzn: I dislike area51 for perhaps the opposite reason: it makes it too easy to try to start a community instead of encouraging peopel to join existing communities.

vzn

maybe ppl have attempted to join existing communities & get rejected

se culture is restrictive & compartmentalized

at times

Wandering Logic

Perhaps. For the OS/Compiler/PL proposals you can see in the "Followers Active In" stats on the side that CS is not in the top 6.

vzn

little or low toleration for diversity

Wandering Logic

I think it's more that they didn't know that CS exists.

(And certainly don't know that scicomp exists)

vzn

5:23 PM

yeah well thats the issue of site promotion which weve discussed lots on chat

Wandering Logic

But we (here on CS) can be kind of hostile

vzn

exactly, but that is true of every se site it seems

dont see a solution but think you are asking the right questions.

se suffers from "when you have a hammer everything looks like a nail"

there are lots of hammers in se...

downvotes, closing questions, banning users, etc

deleting comments/questions....

poof

migrations...

editing users questions to strip out stuff....

Wandering Logic

I think we do all that stuff, but mostly to neophytes.

vzn

if you look at the mass users on a se site, the rep is low. therefore essentially most users are neophytes.

my pt is that how neophytes are treated determines whether they come back.

Wandering Logic

I meant neophytes == undergraduates

vzn

5:28 PM

if their 1st experience is bzzzt, zap then they are unlikely to come back.

Wandering Logic

I agree that if you zap someone they are unlikely to come back

And if bringing up the newest questions link gives you a page with questions mostly on hold you are going to be somewhat put off.

Not that I actually think we are particularly overly aggressive about closing questions.

Most of what gets closed is really bad questions.

But what I'm particularly worried about is how we attract a critical mass of experts in applied cs.

We are really strong on algorithm design and analysis here

and also strong on PL

vzn

agree most closed questions are borderline but doubt it has much to do with attracting experts.

Wandering Logic

but there aren't many of us here who publish in conferences like CGO, ISCA, MICRO, OSDI, SOSP.

vzn

mods argue that borderline questions make experts flee, but kind of doubt that.

its one of those articles of se faith circulating among the masses....

the so called shiny quality questions

anyway if a cs site is stuck in beta for a long time, why should a CS subtopic proposal be raised in area51... agree it makes no sense

Wandering Logic

I don't think the problem is too many bad questions

but there is a lack of quality questions in applied cs

vzn

5:39 PM

see it more in terms of attracting quality users rather than questions

Wandering Logic

yes.

but how do you do that?

vzn

the $1M question.

heres a crazy idea.

every time two people on the site disagree about something, it loses )( that much momentum.

find a way to agree....

se seems at times like a disagreement machine....

my zen question, is it the software design or human nature?

or both?

just some crazy musings from the court jester.

Wandering Logic

My favorite Area 51 proposal: area51.stackexchange.com/proposals/60952/trolling

:-D

vzn

funky

that reminds me of a cogsci question

high voted

21

Q: What is the psychology behind trolling?

For those new to the internet, trolling is an activity where one person intentionally tries to upset other members of the same community, presumably for entertainment. This has been informally addressed in the media, normally positing that the anonymity of the internet gives rise to more extrem...

abnormal-psychology social-psychology internet

its very strange though, cs enrollments are up at colleges at times.

the so called "social network" effect (re movie, seemed to have a bump on CS enthusiasm)

its too bad stats are not kept on failed area51 proposals, its rather staggering.

Wandering Logic

That's a good question.

MAKES ME WANT TO PICK A FIGHT!!!!

vzn

5:47 PM

lol

Wandering Logic

;->

vzn

← subversive & likes fighters =D

yeah area51 is something like a big semisticky flytrap

Wandering Logic

There have been some resounding successes (outside of cs)

vzn

on area51? like what?

anyway se has never been a lot about building new communities its more about trying to get ppl to fit into existing boxes....

Wandering Logic

I think Gaming, English and Cooking.se all came off Area 51.

vzn

5:50 PM

actually almost all sites came out of area51 afaik.

100+ sites now.

it is impressive.

se mgt seems to have no response for many sites stuck in beta though.

Wandering Logic

I think we're closer than we think.

vzn

its just endless "wait and see"

Wandering Logic

I don't know how to search in this chat room

vzn

upperright search box.

the search is indeed tricky.

Wandering Logic

but there was just a post a week or so ago where they said that the only remaiing bottleneck is getting a graphic designer freed up for us

vzn

5:51 PM

also click info tab.

yeah shog9 might have been saying that.

am doubtful the site is not graduating because of the graphic designer.

gilles was talking a lot about the design iirc.

like your team spirit yay go team

thx for the info re parallelism, have found it highly fascinating subj for yrs.

sounds like youre working on some cutting edge stuff.

Wandering Logic

Thx

vzn

yrs ago knew guy who went to work for intel, had phd iirc

an amazing company

do you do any research there?

Wandering Logic

Not much research. More prototyping and advanced design.

I never much liked writing papers when I was an asst. prof.

(which is probably why I'm not an asst. prof. any more)

vzn

lol

what languages are you using?

Wandering Logic

I get a really good intern now and again who will write a paper with me.

vzn

5:58 PM

cool :) looking for good interns myself in meta lol

Wandering Logic

dl.acm.org/citation.cfm?doid=2000064.2000084

Languages: we do most of the tool dvpt in C++

Languages we analyze gets weird

Pin handles machine code

And we can handle the standard debugging symbols on Windows and Linux

vzn

←have debugged tricky race conditions over yrs & answered few questions related to it/parallelism etc

Wandering Logic

But on the GPU side it's a mess.

vzn

re area51 there is an interesting feature where when the proposals fail, existing mods are allowed to "poach" the questions.

Wandering Logic

We're trying to work with OpenCL, Intel(R) Cilk(TM) Plus, OpenMP 4 simd pragmas

vzn

6:02 PM

gilles did that a bit with the AI proposal.

Wandering Logic

I saw one of those the other day.

vzn

not sure how many questions came out of that.

guess its easy for them to "skim" the highvoted questions.

so all is not lost.

Wandering Logic

An AI question that got migrated from the failed AI site

vzn

yeah.

se basically does not try to support "small" communities much.

its all about scale.

Wandering Logic

I wish we could get the people to migrate in with the questions/answers

vzn

6:03 PM

have seen shog9 even complain about tcs.se being too small in a meta post.

would like to see se experiment with smaller, more dedicated/passionate communities more.

have collected tons of refs on se culture, planning to blog on it sooner or later. blogged on it once, re the hair-trigger closing tendency cross-sites.

like facebook, "its complicated"

Wandering Logic

Math Overflow gets 42 questions a day

vzn

yeah. think thats kind of cool. think the slow moving sites (cs.se, tcs.se) are kinda less interesting.

Wandering Logic

TCS gets 8.5 (which is much better than it was a year ago.)

vzn

math.se is another huge success story, moves fast, relatively new site.

Wandering Logic

I think Math Overflow and Math are the golden standards

vzn

6:06 PM

MO is quite the phenomenon and largely inspired tcs.se.... tcs.se is still a MO "wannabe".

never will reach MO scale.

Wandering Logic

There's a new Mathematics Educators beta that seems to be doing quite well.

vzn

the MO experts are incredible. real top leaders in mathematics.

Wandering Logic

Maybe Mathematicians are nicer people than Computer Scientists

vzn

yeah have dinked around a bit on the math edu site.

lol.

MO is brutal as far as killing off marginal/borderline stuff, even more so than many se's.

its an extraordinary case that shows there can be a huge amt of experts and very high constraints on quality.

Wandering Logic

As well they should (given the existence of math.se)

same for tcs

vzn

6:08 PM

actually math.se and cs.se arose after the elite sites MO/tcs.se were created 1st. but yeah.

Wandering Logic

I think that in this case the "quality questions" thing is releavnat

vzn

yes, basically agree.

Wandering Logic

Yes, I know.

It's actually backwards.

vzn

have asked research questions on tcs.se and still gotten heavily roughed up over them.

Wandering Logic

MO is the core, and math is the "overflow"

vzn

6:09 PM

its not just research but elite research sometimes.

←always a bit terrified to ask questions on tcs.se/MO even after yrs of doing so.

Wandering Logic

I've never asked a question on either.

vzn

so yeah, have a huge luv/hate relationship with se myself.

some days luv/hate other days hate/luv :p

Wandering Logic

:)

vzn

the software capabilities/features are amazing/awesome at times. the use of them (by humans) is whats often killer

have you heard about the new meta stackexchange reorg?

you can try raising some issues there.

bzzzt, zap j/k :p

Wandering Logic

Yes, I saw the meta reorg.

vzn

6:16 PM

Blog - Stack Exchange: Announcing The Launch Of Meta Stack Exchange

Tim Post on April 17, 2014

We’re very pleased to announce that as of today, we’re (finally) splitting the site formerly known as Meta Stack Overflow into two sites:

Meta Stack Overflow is a brand-spanking new site for discussions specific to the Stack Overflow (programming) community:

Meta Stack Exchange will cover feature requests, bugs, and any discussion topics that affect the entire network:

Meta has always been one of the most important things that make our network… work. Almost all of our most important features, improvements, and community rules were partly or entirely based on our users telling us how we could help …

whole new playground

with brand new bullies :p

meet the new boss, same as the old boss =(

Wandering Logic

Speaking of "boss"...

The phone meeting that I looked like I was attending just ended.

vzn

hah ok

Wandering Logic

So I had better actually do some work now. :p

vzn

me2 nice chat l8r smart dude

Wandering Logic

you too. thx!

vzn

6:22 PM

=D

a zen question to ponder, if undergrads arent allowed to ask about hw on this site (the main audience) then how can they use it, how do we draw em in, make it "sticky"?

vzn

9:56 PM

alas, se is in many ways the "only game in town right now". :(

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