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Slashback: Cheaters, Spammers, Chessmen 352

Posted by timothy from the unclehood dept.
Slashback brings you more words tonight on catching CS cheaters (and whom to credit for the software that does so), giving money near-painlessly to another worthy cause, complications in wiretapping California's phones, and more. Read on, and enjoy!

GA Tech TAs not given credit for program exposing those who don't give credit. zorba1 writes: "Chalk another one to the 'TAs get no credit' department. CNN is running an article on how on how Georgia Tech's College of Computing professors wrote a cheat-finder program that discovered 186 Intro to Computing cheaters. As a former CS TA at GaTech, some clarification points:

  1. The app was developed by TAs, not by professors.
  2. It doesn't detect 'exact duplications of computer code.' It removes variable names and examines duplication in code structure.
  3. The only reason it's in the news is that GaTech recently required nearly all students to take one or two introductory CS courses."

The stench whiffed 'round the world ... Kelsevinal writes "A look at this article on the Chicago Tribune website reveals that our good friend Bernie Shifman is getting a little publicity... Think what you want about the situation, but I think it's funny as hell. I bet Shifman likes it too ... think of all the human resources depts. who might see this!"

After all, not everything is Free. xueexueg writes: "I just noticed that the Free Software Foundation has finally gotten around to setting up secure servers for orders and donations. For ages you actually had to print out and mail an order form to them, but now, at last, you can give them money for goods or charity, in your proverbial underwear."

And let's face it, there aren't that many places in the world where you can order T-shirts adorned with a levitating gnu.

Does this remind you of Gorman Seedling's electric collars? koganuts writes: "Updating a story posted by Slashdot on January 9th, according to The Los Angeles Times, "Gov. Gray Davis' proposal to let state and local police obtain roving wiretaps on suspected criminals was dropped from the legislation containing it Tuesday after the legislative counsel's office concluded that it was illegal." There were also provisions in the proposed bill which extended wiretapping to e-mail and the Internet. One thing I never knew was that "...wiretaps cost an average of $56,767.""

Have you learned your lesson? Eblis writes: "The Learning Machine Challenged hosted by AI has finally ground to a halt, with results available at lmw.a-i.com. Congratulations to the winners and to AI for hosting such a successful contest!"
This discussion has been archived. No new comments can be posted.

Slashback: Cheaters, Spammers, Chessmen More

Slashback: Cheaters, Spammers, Chessmen

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  • The only reason it's in the news is that GaTech recently required nearly all students to take one or two introductory CS courses.

    And people are complaining about this? No one forced them to go to a technical school or anything ...


    • Similar problems generally have similar solutions, expecially when every person producing that solution was taught by the same instructer. It is very likly that many of these programs would share a similar structure overall. Of course, the did not mention how similar it has to be, but I would not bet on this program only catch actuall cheaters, allot of dolphins probably get caught in that tuna net.

      • Assume the assignments that they're bothering to check are at least decently large ones, and not first day "Hello World" apps. In even a 200+ line program, there are enough different ways to structure a function, phrase an algorithm, manage a sort, etc. etc. that i think it would be doubtful that even in a class of several hundred people, two identically structured programs would emerge.

        I don't see how this is news though. Other schools have had similar software for years. I know for a fact that the Columbia University CS department has it, and I'm assuming others do to; it's a fairly obvious measure.

  • Well worth the $$$ (Score:4, Offtopic)

    by Guitarzan ( 57028 ) on Monday January 21, 2002 @08:03PM (#2879397)
    If you could pay $56,767 to wiretap a 900 number, imagine how much cash you could save!

  • CS cheaters? (Score:1, Funny)

    by Anonymous Coward
    Aw crud! I thought you mean't CounterStrike... :(

  • To take care of some spammers! (Score:4, Offtopic)

    by www.sorehands.com ( 142825 ) on Monday January 21, 2002 @08:10PM (#2879433) Homepage
    When I get the SPAM for the software to make unlimited copies of DVDs so I never have to pay for a DVD again, I forward it to hotline@mpaa.org [mailto]. See if the MPAA is really after piracy, or just to scaare people.

    • Re:To take care of some spammers! (Score:4, Funny)

      by aridhol ( 112307 ) <ka_lac@hotmail.com> on Monday January 21, 2002 @08:34PM (#2879561) Homepage Journal
      When you do this, make sure of one thing - ensure that you make it absolutely clear that you are forwarding an email you received. You don't want them coming to sue you for spamming and copying DVDs when you're trying to report someone.
    • Heh, you ever /read/ the message's claims though?

      It says that their software allows for you to burn DVD-Rs with your CDR burner! LOL!!

      One of the newer varations appears to be selling instructions on how to copy from DVD to VHS.

      (This isn't all that hard really, if you have a CDR drive and a DVD-ROM drive on your computer and a standalone DVD player, it will just end up looking like dog shit. Rip the DVD, decrypte, reencode into SVCD or VCD [eew] and then play said S/VCD on your DVD player, which most now days support doing. Plug your DVD players out into your VCRs in and set the VCR to record, you will have to pause the recording while swapping S/VCD disks unless it is a /really/ short movie, but besides that. . . . enjoy your pixalated blurry mess! ^_^ )
    • Hah!

      I saw this spam for the first time, today. I figure they are just selling a program to copy the DVD data onto CD-R media (perhaps DivX encoded), but I tried to read all the fine print and couldn't find any reference at all to the fact the result wouldn't be a DVD.

      Ifso, then near as I can tell, the ad is fradulent.

  • "I just noticed that the Free Software Foundation has finally gotten around to setting up secure servers for orders and donations."

    I wonder why they didn't previously use a service like PayPal for donations. It's used by many sites for secure transactions, for example ebay.com.

  • Question... (Score:2, Interesting)

    by Anonymous Coward
    $56,767 per wire trap?

    Is this just another made up number that if repeated enough people will assume that it is true?

    What does this include...
    FBI Agents pay check? Judges? Infrastruture cost in the FBI, that would cost the same if there were 2 wiretaps vs 20? DA's paycheck? Is this offset by any bribe money?

    Did they take the entire FBI budget and divide by the number of wiretaps and come out with a number that way? Which if were true then not issuing 2 wiretaps would save 100k+ a year..

    • Re:Question... (Score:5, Insightful)

      by filtersweep ( 415712 ) on Monday January 21, 2002 @08:39PM (#2879585) Homepage Journal
      "A recent report by the state Department of Justice showed that California law enforcement requested 88 wiretap orders in 2000. Judges granted every request. The wiretaps cost an average of $56,767 and resulted in the arrests of 271 people. Of those, 17 were convicted. Most were used in drug investigations and involved home phones, cellular phones and pagers. "

      I'm just spitballing here, so bear with me...

      88 wiretaps = 271 arrests = 17 convictions, 254 that were NOT convicted

      88 wiretaps requested = 88 wiretaps granted (not a bad percentage)

      88 wiretaps X $56,767 = $4,995,496

      $56,767 / $40hr = 1419 "man" hours per case on average (OK... I just made up $40 for maintaining an employee with benefits, etc...)

      That is a hell of a lot of time put into wiretaps. If taps are anything like most businesses, the real cost goes into employee time. I probably spend a total of 25 hrs./month on the phone (including work time... and one might assume criminals might consider crime as part of their job?). If an investigation takes 10 months, we are up to 250 hours. If we consider the ratio of 88 taps yielding 271 arrests, that is about 3 people per tap. If we multiply our 250 hours X 3 we are at 750 hours... and that is just real time phone monitoring. Add all the support staff and forensics- we'd have to double that staff time to bring it to 1500 hours per case. It might actually be plausible.

      More significantly I find it disturbing that 100% taps are granted by the courts, but the conviction rate is about 19%. The arrest to conviction rate is 6%. That is a low return for giving up civil liberties.

      • Of course you realise that's $300,000 for every drug dealer put in jail, just for the phone taps. Anyone still think the drug war is worth it?

    • Re:Question... (Score:3, Interesting)

      by spongman ( 182339 )
      56767 looks more like someone typing a series of five digits with three fingers.

  • Money in my underwear? (Score:4, Funny)

    by GeekLife.com ( 84577 ) on Monday January 21, 2002 @08:12PM (#2879445) Homepage
    Well, I'm glad they finally take that online (though I'd like to hear how) 'cause the Postal Service was really getting peeved at me for trying to send all that underwear through snail mail.
  • "We've all been looking for a spamming village idiot to be pilloried in the town square," Schwartzman said. "Now we've been blessed with Bernie."

    I would say that the newspaper article has about trashed his odds for a regular job.

    Hopefully he will leave the country, and move to Brazil. I understand there is an area down there the government is trying to turn into the Silicon valley of South America.

    They are bound to need a few good consultants.

    • I'd guess he's either already spammed the folks in Brazil and pissed them off, or he soon will.

    • Comment removed based on user account deletion
  • A teacher of mine told me they were using a program such as the one mentioned here to check for cheaters in one of my programing class's at the University of Calgary.

    • Re:my school (Score:5, Interesting)

      by jovlinger ( 55075 ) on Monday January 21, 2002 @09:40PM (#2879846) Homepage
      I graded an introductory scheme course once. You have no idea how easy it is to pick out cheating in an introductory programming course. You can actually pick out pretty much the whole solution history, much like a genetecist can track speciation through differences in DNA.

      Beginning programmers make such a wide range of mistakes that it's obvious which people discussed the problem before hand, which people programmed their solutions sitting next to each other on different computers, and which people just made a copy of someone else's solution (while they were away from the computer, it is often claimed).

      I'd say that all but the last of these scenarios is fine. What IS galling - nay insulting - is that they students think that the TA won't notice that two programs have exactly the same error epidology. I could understand if they thought they could get away with copying and modifying a working solution, but when the solution doesn't produce the required result, the TA HAS to grok the code. And you quickly notice when solutions are "similarly stupid". Strangely enogugh, the right solutions tended not to be copied. I'll spare you my specualtions on the social dynamic that results in that scenario.

      So no program necessary, IMHO. Of course, I had a fairly small class. I would hope that bigger classes get a couple of TAs.

      • Re:my school (Score:2, Insightful)

        by sholden ( 12227 )

        What IS galling - nay insulting - is that they students think that the TA won't notice that two programs have exactly the same error epidology. I could understand if they thought they could get away with copying and modifying a working solution, but when the solution doesn't produce the required result, the TA HAS to grok the code. And you quickly notice when solutions are "similarly stupid". Strangely enogugh, the right solutions tended not to be copied. I'll spare you my specualtions on the social dynamic that results in that scenario.

        So no program necessary, IMHO. Of course, I had a fairly small class. I would hope that bigger classes get a couple of TAs.


        The problem arises when there are too many students. Sure you'll catch the really dumb students who copy someone in their own class, or who has the same TA. But those students will fail the exam anyway and hence won't pass even if not caught...

        You won't catch those students who copy someone in a different class with a different TA, since you won't see the other almost identical solution.

        In my experience some of those students are found, because copying seems to spread, and usually a group of students have 'similar' solutions, so when you happen to get two of them, you can grep for whatever the magic phrase is that really gives the game away in the submissions of all the students and probably find a few more matches.

        The last course I taught had ~650 students. I lectured the course (wrote the material, gave the lectures, wrote the assignment specs, did the machine marking, etc), but didn't take any of the tutes/labs and hence only did the hand marking of assignments which were late for whatever reason, or for students whom the enrollment database refused to believe were in a tute...

        As always some students cheated and some of those were caught (some got away with it no doubt).

        I think one tutor (I think our equivalent of a TA) reported students he suspected of copying, and only a couple at that. So the tutors didn't find many - since they only marked a small percentage after all...

        A handful were caught because I happened to mark two assignments that used malloc (in a C++ course that never mentioned it even in passing) in identical wrong ways. And grepping for malloc found a few more *very* similar assignments.

        The majority of those caught were found using two simple little programs called sig and comp. Sig takes the submission as input, splits it into chunks and outputs simple hashes of those chunks. Comp compares the hashes of a bunch of submissions and says which are similar.

        Submissions that score high with sig/comp *always* look very much like they have been copied. Those that score low *always* look very much like they are different. Those that score in the middle consist of both. Hence it misses some cheats, but more importantly doesn't generate false positives very often.

        sig/comp was actually an assignment for out Software Engineering course a few years ago. Rob Pike (on sabatical teaching in out dept for a semester) was annoyed enough at teh apparant cheating in one assignment, that he set writing them as the next assignment and used the previous assignments submissions as the sample data. This did seem to show students that cheating was easily discovered...
      • So no program necessary, IMHO.

        I couldn't agree more. Especially considering this was an INTRODUCTORY course (or did I mis-read?). Let's face it, intro programs tend to be SMALL; there are only so many ways you can write a recursive factorial function, and in a class of several hundred students, chances are 2 of them will duplicate a LOT.

        A keen TA is worth a lot more than just accusing students of plagarism based on coincidental code. Case in point: my brother and I both wrote one of my 1st year assigments. The programming guidelines were rather strict (I guess this keeps the TA's from having to spend much time grokking weird code), so the basic framework was pretty much set out for us. Now, both of us come from the same school of thought regarding implementation/testing/debugging, but still...

        Our programs had several lines that were identical. Not just close; IDENTICAL. This in what amounted to maybe a 50 line program. The rest was similar enough, that if you DIDN'T look for the differences, you wouldn't have seen them. Thankfully he wasn't enrolled in the class with me at the time...

  • DAMN!!! (Score:2, Funny)

    by SuperguyA1 ( 90398 )
    Slashback brings you more words tonight on catching CS cheaters

    Damn! I thought I was finally going to be able to start playing Counterstrike again without all the freakin cheating! Turns out it's just some school thingie... Sigh.

  • i was hoping you guys would have news about catching COUNTERSTRIKE cheaters, not COMPUTER SCIENCE cheaters.

    *sigh*
  • University of Illinois at Urbana Champaign had similar cheating catching software running on all the programming assignment since before 94. This is nothing new. I remember in 96 they caught 2/3 of the intro CS class (those silly non-CS/CompE majors) copying code from each other.

    • some intentionally dont (Score:3, Informative)

      by Anonymous Coward
      I know that at least one university (the one I am still enrolled at, hence the anonymous coward...) intentionally looks the other way when students send in copies. Why? Two reasons.

      1. It makes the university money.Alot of the computer science freshmen turn in 'very similar' coding assignments. They pass a class or two in this manner, but later fail a couple project oriented classes that they can't fake. Then they change majors once or twice, taking that many more classes at the university. More classes = more money for the university. (note: a professor told me this- if this reason is BS then it his his BS, not mine.)

      2. If you punish one cheater, you have to punish them all. Look at the stats they are giving - 2/3 of the students cought? The school is chucking it's reputation. It also takes extra work punish these students, the professors have to attend boards of inquiry and such. (This explanation also came from the same professor, but seems like a more sane responce than number 1.)
    • In the giving credit where it's due department, MIT has been running similar programs since 1990. It was a big deal back then, since they caught a quarter of the class. See the article [mit.edu] from The Tech [mit.edu], MIT's newspaper.
      • Same thing back when I was doing Comp Sci at the Australian National University back in '91. It was our lecturer's pet project and he once spent half a lecture drawing tree diagrams of who had copied from who and how is program had detected it.

  • Shifman article seems biased (Score:4, Insightful)

    by Shade, The ( 252176 ) on Monday January 21, 2002 @08:18PM (#2879485) Homepage
    The Chicago Tribune seems to represent Shifman as a guy who's been persecuted by the devilish anti-spam community. Um, hello? Read the log of emails sent back and forth. Shifman is abusive, insulting and, quite frankly, stupid. He seems ignorant of any legal knowledge whatsoever; threatening to sue all involved in critisising him for simply reporting a piece of spam _he_ wrote.
  • Did anyone else read catching CS cheaters and think of the newest software going around to catch counter-strike cheaters? seems to detect everything but ogc6 and later.

  • Please stop and vote for this moron spammer (Score:4, Informative)

    by anticypher ( 48312 ) <anticypher@@@gmail...com> on Monday January 21, 2002 @08:19PM (#2879501) Homepage
    Cool, the Chicago Trib has a poll, just like slashdot and cNet.

    Is Bernard Shifman a "moron spammer?"

    Yes. Hundreds of complaints can't be wrong.

    No. Give the guy a break. He's looking for a job.

    Please stop and vote for this moron spammer.

    the AC
  • For a moment I was wondering why everyone at Georgia Tech's Computer Science department was playing CounterStrike. Coz of this statement:

    "Slashback brings you more words tonight on catching CS cheaters..."

    After all, EVERYONE playing CounterStrike cheats, right?

  • Similarities in Structure? (Score:5, Insightful)

    by rMortyH ( 40227 ) on Monday January 21, 2002 @08:25PM (#2879526)
    I'm interested in this GA tech program....

    I have alot of hours in as a helper in undergrad CS labs. If you were to remove the variable names in intro to CS assignments, most correct assignments should appear identical without cheating, especially given the simplicity of such projects. Are thirty classmates supposed to come up with thirty completely different and original programs to calculate a fibonacci series? Is that even possible? Does anyone have any information about false positives?
    • You've hit the nail on the head (though this has been discussed before plenty). Something like this is going to do more harm than good in an intro computer science class because the programs will all be virtually the same in design. Perhaps in a large, upper-level class it would make sense, but the again, no professor's I've ever had (or TAs for that matter) have had much trouble spotting identical "structure" on students' assignments.

      • I beg to differ (Score:2, Interesting)

        by AndyChrist ( 161262 )
        Copying code is a WORSE offense in a beginner's class, because these are people who are for the most part never going to progress beyond this in programming, so won't have opportunity later on to learn the lessons they should be learning now.

        By copying each other's code...or more likely everyone copying one person's code, they are making it less likely that most people will learn the basic concepts of how a program works, even on a high level of abstraction.

        They'll just be Lusers who can say they completed CS coursework.

        A CS senior should already know what functions and variables and whatnot are. A freshman biology (or whatever) will not, and they won't learn later.

        And don't think for a second that this doesn't help a person understand better how to be a better end-user.
        • Who said anything about one being a worse offense or another? I stated more harm than good would be done by this software (meaning false accusations versus actual copying offenses) in an introductory class where all the students are completing the same basic assignments with few ways to go about completing them, versus students copying larger, complex assignments line for line. I agree with your points completely, but they weren't what I was addressing

    • Re:Similarities in Structure? (Score:5, Interesting)

      by Tom7 ( 102298 ) on Monday January 21, 2002 @08:46PM (#2879624) Homepage Journal
      One of the tricks we used (at my school) was to look for trailing whitespace and the combination of leading tabs and spaces, since this kind of thing is preserved when copying, invisible, and unlikely to be the same across independent correct solutions. It's true though that this automatic testing can't do much for the really simple assignments (ie, write insertion sort).

      Much better was simply (when possible) assigning the same person to grame the same piece of code across all assignments; certain bizarre idioms or mistakes really jump out at you and catching cheaters that way is much more effective.
      • my school had a neat trick called exams. those who couldn't program didn't do so well.
      • For those trivial assignments such as generate a list of fibonacci numbers or primes, or compute the factorial of an arbitrary input number, a fun approach for the lab assistants might be a trivial interpreter which interprets a trival bytecode in which is written the trivial assignment. All as a neat compact little program with an array initializer of the data which actually implements the algorithm. Explain to the prof. how it works.
    • I've run similar programs (at UC Berkeley) that check for structure of student's programs. I don't have numerical analysis of the results, but from my personal observations, anything that hit above 30% on the similarity level was almost always valid in one way or another. (maybe not blatant cheating, but too much collaboration, etc.)

      Of course, we only used this on projects, which tended to be much larger than homeworks. (i.e., we would never ask them to just calculate the fibonacci series, more like pseudo-Life simulations, games, etc.)
    • I used to run a similar program at my old school to check for cheats. I never got to see the internals, but I believe it was quite similar to the other ones described. You could manually set a threshold "similarity value" which was reported. We always manually checked any "overly similar projects" flagged by the system, and, with an appropriate similarity value, its false positive rate was damned low (probably 90% of the people it flagged were definitely cheating, and the other 10% were probably doing so). This was on ~200 lines-of-code introductory projects in C and a functional language called Haskell.
    • Actually, there are an infinite number of different and original possible programs to calculate a fibonacci series. Computer science at work!

    • Re:Similarities in Structure? (Score:5, Informative)

      by Anonymous Coward on Tuesday January 22, 2002 @12:13AM (#2880302)
      Disclaimer: I too am an ex-TA from Georgia Tech. I am posting this anonymously due to possible privileged information.

      The CheatFinder is really a suite of programs, sort of kludged together. Some are writting in various shell scripts, other parts are in C and Perl. In a nutshell, CheatFinder examines all permutations of students' submissions and calculates a score from 0.00 to 1.00, where 1.00 indicates a perfect match. The one in charge of running CheatFinder determines a relevancy level, typically 0.95 or so. All results above that threshold are then hand-examined for matches -- things like same indentation, same errors, etc. For students whose works were flagged by it, all of their other submissions were then critically examined. The idea was to build a case to demonstrate that this particular set of students were cheating, much like Jack McCoy builds a case for the prosecution. The true test to see if a person was cheating was by asking him/her, "Tell me how your program works."

      As you correctly pointed out, simple programs will cause multiple false positives. CheatFinder was not run on those trivial assignments; it was reserved for the longer ones occuring later in the term.

      To be honest, CheatFinder was just one of many ways to detect academic dishonesty. Experience has shown that cheaters are stupid. Examples include: forgetting to remove their friend's name from their submission, braggingg about their exploits within earshot of a professor, and so forth. Almost of our cheaters were found through means other than the CheatFinder.
      • As you correctly pointed out, simple programs will cause multiple false positives. CheatFinder was not run on those trivial assignments; it was reserved for the longer ones occuring later in the term.

        I'm just amazed that an introductory class for _everyone_ manages to get as far as non-trivial assignments -- unless Georgia Tech simply accepts that certain freshman aren't going to make it...
        • unless Georgia Tech simply accepts that certain freshman aren't going to make it...

          I don't know about Georgia Tech, but when I was a Michigan Tech in the mid-80s there were definitely weeder courses. Chem 101 was a biggie. It was made intentionally hard to weed out students who really shouldn't be in an engineering school in the first place.

          Of course, the average snowfall of over 200 inches per year and the 4:1 male:female ratio were also discouraging to many... :-)

        • I'm just amazed that an introductory class for _everyone_ manages to get as far as non-trivial assignments -- unless Georgia Tech simply accepts that certain freshman aren't going to make it..

          Georgia Tech is a great school. It does things the right way. It's fairly easy to get in, but it's non-trivial to pass. Those who don't put in the effort don't pass.

          About 1/3 of the freshmen fail out or transfer out.

          Contrast this to Harvard (note: I haven't gone to Harvard, but my friend did and this is what she told me) where they are very selective for admissions, but they make it much easier to pass -- it's still hard to do well, but easier to slide by. At GT they curve around a C in many classes (as many people get Fs as As), instead of a B (more people get As than Fs-Cs).

          • OK, I understand this better. At Oklahoma State, the first year engineering courses weeded out about 2/3 -- but there were plenty of easy majors in other departments, so most of the eng. dropouts didn't drop out of the university. GT may not have the education, literature, and other soft majors at all.

            It sounds like GT's decided that anyone lacking the "tech" ability to learn to program in one semester is at the wrong university.

            And yes, I have a pretty good idea how easy it is to slide by at Harvard or Yale if you somehow get in, by looking at certain graduates who must have got in by family influence. Gore went to Harvard and obviously has been educated far beyond his intelligence, while GW Bush went to Yale and (although not stupid) shows no signs of being educated at all...

    • Re:Similarities in Structure? (Score:5, Insightful)

      by firewrought ( 36952 ) on Tuesday January 22, 2002 @12:35AM (#2880385)

      Allow me to present some random thoughts in defense of GA Tech's cheatfinder:

      First, the program is used to finger potiential cheats... all suspects are examined by humans who are aware that the cheatfinder may report false positives. It's not as if the cheatfinder automatically files charges with the Dean's office. In this sense, the cheatfinder serves to augment (not replace) human intelligence in a way that would otherwise be infeasible in a class with 600 students.

      Second, the assignments are non-trivial, so design can vary substantially. Even when the things are simple, it can be awful damning when two people choose the same design approach to all problems on their homework (especially when the problems are conceptually independent of each other, or when two students' answers share the same monstrously silly mistake).

      Third, an incredible number of people cheat; most of these people don't get caught, or if they are caught, they don't get punished, or if they do get punished, it's a light wrist-slap for the first offense (say... receiving an "F" in the class and a note on the transcript instead of expulsion). Because The College of Computing [gatech.edu] has a program, they catch the highest number of cheaters. I feel sorry for all of the honest students (especially those in the harder majors) who must compete against cheaters their entire academic career: their degree is devalued in the marketplace by the behavior of others.

      Fourth, the cheatfinder program recognizes and adapts for common structures in student programs: if fifty percent of the class shares a common structure, there are at least three explanations: (1) fifty percent of the class coluded with each other, (2) the problem is "naturally constrained" so as to be most readily solvable in this one fashion, or (3) the professor goofed and gave the problem as an example in class. Cheatfinder is smart enough to realize that (1) is unlikely, and so considers the duplicated structures to be innocent. So if the entire class cheated and turned in the same exact assignment, the cheatfinder would not report it.

      Fifth, counter to some suggestions by fellow slashdotters, it is best to run this thing at the lower levels of the program. The higher level classes aren't focused on "how to program" and generally don't afford as many opportunites for cheating (many, but not all, of GA Tech's 4000 level classes have every student-team work on a different project). At the higher levels, code reuse can be a good thing, provided that proper credit is given to the real author and that the essential learning challenge is not removed.

      Now for the disclaimer: I am a Georgia Tech TA, but I have not had direct exposure to the cheatfinder. Most of my claims are based on heresay and private conversations with those who do work on the cheatfinder. Some claims are based on my own experience TA'ing and trying to prosecute people.

    • my point is this exactly. Teaching a simple bubble sort. most of the students will have it nearly identical if they did it right. The kid in the corner that gave you obfuscated C that is all on one line, while is bright, needs to be beaten with a stick. I am against any type of automated detection like this. it instantly calls all students cheaters and then makes the students prove they did not cheat by submitting to the system. I have ZERO respect for any instructor that would use a cheating detector like that.

  • CS Cheaters (Score:1, Redundant)

    by mESSDan ( 302670 )
    Slashback brings you more words tonight on catching CS cheaters

    I was very impressed that the people who cheat at Counterstrike were finally going to be caught! (As opposed to those people who use Punkbuster, where the cheating may only be averted) I figured it's about time since the latest version of Half-Life features Opaque Walls [themushroom.com] (Finally!).

    To think that I was wrong, this was about people cheating the people who wrote the program that caught cheaters! heh ;)

  • The lesson Bernie didn't learn... (Score:5, Insightful)

    by Restil ( 31903 ) on Monday January 21, 2002 @08:29PM (#2879549) Homepage
    Once upon a time, I was a member of a mailing list and I posted a rather controversial message. Someone replied telling me how much of an idiot I was. I responded privately to him, attempting to explain why I felt I was right and based it on my own personal (yet somewhat embarrasing) history. I kept it off the group primarily because I mentioned issues I felt I really didn't want the whole world knowing about and also I didn't feel like carrying on a public flamewar.

    Needless to say, he decided to post a reply to it on the mailing list, complete with my message fully quoted. NOT what I wanted to happen. Of course, the response was less than friendly. I could have decided at this point to reply again, either to him or to the group (same thing really) and continue the war, but instead I just dropped it. Completely. A few people responded once, but in a day the thread was dead and I doubt anyone remembered it.

    Bernie started out by doing a stupid thing. He spammed a bunch of people trying to advertise his "services" through what he STILL seems to believe is a reasonable method and when confronted chose to reply and carry on the problem by REALLY making a name for himself.

    What if he just let the issue drop? If he just quit spamming and never said another word about it? In a matter of a couple days nobody would ever recognize him. Whatever little damage was caused by a letter to his isp would have been the extent of his embarrasment. He could have EASILY picked up the pieces from that debacle and avoided further problems. Now, its getting to the point where he may very well be unemployable in his industry of choice because not only has he made a professional ass out of himself, he is causing people to look VERY carefully at the type of work he supposively has experience with and relating it to his behavior in this matter and creating the (probably correct) impression that he is most unqualified for the very positions he seeks.

    If only he had shut his mouth and walked away while he had the chance to do so gracefully. The world is a big place. You have to screw up pretty badly to make a name for yourself. I despise spammers as much as the next guy, but its a foolish mistake he could have recovered from easily. Now he won't live it down for a LONG time.

    I hope fame was what you sought dear Bernie. For you have found it.

    -Restil
  • Hey, most spammers are severely non-bright. Why else would they think spam is an effective way to advertise? (Actually, it is an effective way to sell spam software, since there are so many clueless people out there. But that's the exception that proves the rule!) So, obnoxious as they are, it's a little silly to get mad at spammers. Stupidity is a fact of life -- and I've got the scars to prove it.
  • Is Bernard Shifman a "moron spammer?"

    91.6% -- Yes. Hundreds of complaints can't be wrong. (456 responses)

    8.4% -- No. Give the guy a break. He's looking for a job. (42 responses)

    498 total responses

    • Re:10-to-1 odds (Score:5, Funny)

      by servasius_jr ( 258414 ) on Monday January 21, 2002 @08:57PM (#2879681)
      Is Bernard Shifman a "moron spammer?"

      91.6% -- Yes. Hundreds of complaints can't be wrong. (456 responses)

      8.4% -- No. Give the guy a break. He's looking for a job. (42 responses)

      498 total responses

      How dare you repeat such lies?!? This is slander! this is libel! I'll sue you! I'll sue the Chicago Tribune! I'll sue all 456 respondants who answered 'yes'! I will also be suing Al Gore and Bill Gates for inventing the internet, and the moderators and editors on slashdot for violating my 1st ammendment rights! Please give me your address and phone number, as well as those of all of your co-conspirators mentioned above, so my lawyers can sue all of you.

      Litigiously yours,

      Bernie S.

  • (CS == Counterstrike) = IsntFunny (Score:4, Troll)

    by rasactive ( 528598 ) <<onewland> <at> <gmail.com>> on Monday January 21, 2002 @08:42PM (#2879597)
    I will personally kill the next person who posts some stupid "CS? You mean counterstrike?" and then I will kill the person that laughs at it.

    • MOD PARENT UP (Score:2, Funny)

      by Anonymous Coward
      Honestly, everyone should pay attention! About 60% of the posts so far have been this lame CS shit. I'm getting really tired of the idiots in EVERY STORY who get modded up to (+5, Funny) by saying "Did anyone else misread the title 'New Winamp Version' and think it said 'Goatse Man Elected President'?" The gag's worn out, kids.
    • "CS? You mean counterstrike?"

      bring it on, bucko.
  • Check out this snippet at the end:

    New on chicagotribune.com

    Get Office suite tools without having to pay for them! Jason Abate of Hostway Corp. explains how the open-source operating system Linux can help at chicagotribune.com/linux.

  • catching cheaters is easy: check the assembly code (Score:4, Informative)

    by Anonymous Coward on Monday January 21, 2002 @09:01PM (#2879705)
    hm, as a former research assistant I can testify about the approach we used to catch cheaters :
    (this was for an assembly language course)
    • Students had to submit their source codes via mail
    • We compiled the code and ran it ourselves (well our scripts did, anyway :))
    • We checked correctness with our test cases.
    • We cheched the number of machine instructions, the number of instructions of each type aso.
    • When in doubt, we used diff.
    • Before accusing someone, we manually checked.


    We had no false positives.
  • Since there seems to be a large amount of confusion in the use of the abbreviation "CS", I propose that "CS" should generally mean Computer Science and that "C-S" should be the general abbreviation for the half-life mod counter-strike.

    So:
    CS == Computer Science
    &
    C-S == Counter-Strike

    Thoughts?

  • False positives with automated cheat detection (Score:3, Interesting)

    by Anonymous Coward on Monday January 21, 2002 @09:19PM (#2879769)
    My friend is a pretty bright fellow and a TA at UIUC. He wrote a cheat detector for one of the classes that turned out to be pretty effective.

    The class requires you to write specific functions with specific names. His perl script would take a student's code, rearrange the functions in a predetermined manner, cut out whitespace, rename variables, etc.

    It would then do pairwise comparisons with the class.

    Typically, if people are cheating, it's rather blatant. If more than some % of the class has the same function implemented in a very similar way, he throws it out as a comparison factor because the function is probably too small or too obvious to implement any other way.

  • Burn the witch! (Score:3, Interesting)

    by Otter ( 3800 ) on Monday January 21, 2002 @09:32PM (#2879814) Journal
    "We've all been looking for a spamming village idiot to be pilloried in the town square," Schwartzman said. "Now we've been blessed with Bernie."

    That's precisely what struck me as so irritating about this whole epsiode. There are two possibilities here. One is that Shifman suffers from some combination of stupidity and emotional disability that's causing him to behave so foolishly. In that case, I find him a lot less distasteful than the mob of nerds who are ridiculing and provoking him, like some dweeby version of the kind of abuse Jon Katz used as a springboard for his new career.

    The other possibility is that the whole thing is a masterful troll, exploiting the bullying mob mentality of a lot of "anti-spam activists". I would get a huge kick of out of that turning out to be the case.

  • Comment removed based on user account deletion
    • 6 months of 24/7 surveliance? I don't think so. thats 4 full time people making 29k+ a year, working 8 hour shifts and never missing a beat. and thats 29k a year Including health insurance, life insurance (not cheap to provide to law officers) and such, so really only 23k/year... where are you going to find someone qualified to trail a suspect without being caught who'll work for 27k a year when there is already a shortage of police officers, let alone the 4 you'd require?

      keep in mind, also, the 56k figure includes the cost of paying someone to listen to the tapes from the tap and transcribe them...

  • CS Cheaters (Score:5, Funny)

    by Gary Yngve ( 416254 ) on Monday January 21, 2002 @10:17PM (#2879961)
    For one of the classes I TAed at GT, we were too lazy at the time to get the cheatfinder working
    under our conditions... We told the students
    we were using cheatfinder, but we never did.

    We still caught many [lazy/stupid] cheaters.

    There was one time they had to write some
    sockets code and turn in their interactions
    with our test server.

    Bob turned in "Congratulations, gt1234a [Bob's uid] has correctly communicated with the server. You get a 100!"

    Sam turned in "Congratulations, gt1234a [still Bob's uid] has correctly communicated with the server. You get a 100!"

    [names changed to protect the moronic]

    P.S. Zorba... wassup! long time no see!

    • Re:CS Cheaters (Score:5, Funny)

      by zorba1 ( 149815 ) <zorba1&hotmail,com> on Tuesday January 22, 2002 @12:07AM (#2880291)
      I have to admin, the "light test"[1] worked for most of our CS1501 pseudocode submissions (that is, before we went to Scheme).

      [1] 1. Place papers of suspected cheaters on top of each other.
      2. Hold up to light.
      3. Observe how everything overlaps *perfectly*, down to the whitespace, var names, etc.

      PS: Hey Yngve! Not much - email me!

    • Re:CS Cheaters (Score:3, Interesting)

      by J. Tang ( 16252 )
      Hey Gary. What's up?

      I had one student who was failing every single assignment, but then magically turned in a program which ran flawlessly, was multithreaded, and had network support. Needless to say, a few seconds on Google turned up the original -- and uncited -- source code.

      What a dummy.

  • Nothing new (Score:2, Interesting)

    by Eythian ( 552130 )
    Software to catch students copying the code of others has been in place at the university I am at for quite some time. When I was in second year (2000), all our code (in Pascal) was checked against each others using some sort of comparison system. I'm also currently tutoring a first-year introductory programming paper (in Java) where a similar system has just been put in place to check the students code. This is significantly more effective than having us try to spot people who we think are copying, and allows us to pinpoint people early, before it becomes to the harder labs, so giving those who are cheating a chance to stop, and actually learn the material themselves.

  • Phone Tapping (Score:2, Insightful)

    by vmalloc_ ( 516438 )
    "One thing I never knew was that "...wiretaps cost an average of $56,767.""

    LOL.

    I can wire tap a phone with a pair of wire strippers and some alligator clips

    It's about a $10 more job to put a transmitter in it so you can do it remotely

    Typical government overspending.
    • I very much doubt that the bulk of that money is accounted for by equipment. Instead, I'm pretty sure that the bulk of that money is spent on the effort. It takes time to get a warrant, it takes time to hook up the equipment, it takes time to monitor the data, it takes time to analyze the data, and it takes time to get another warrant and start the whole process over when the bad guys mobilize.

    • Re:Phone Tapping (Score:3, Informative)

      by EnglishTim ( 9662 )
      The total cost is always going to be higher, due to the fact that

      a) You'll need a team of people to do it to ensure that they don't get caught doing it... (People watching the house for a while, to work out when the suspect tends to be out... lookouts etc. All of this costs money)
      b) The cost of getting the warrant in the first place (Judge's time is hardly cheap - there's also the cost of the other court personnel who are involved)
      c) The cost of the detectives preparing the case to get the warrant

      etcetera...

      All of this is a good thing. You wouldn't want wiretaps to be cheap, or they'd use them a lot more... ;)
  • Have the class assignment be to write a cheat detector which processes the very same class assignment. Try to cheat *that*!

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