Hacker Exposes Evidence of Widespread Grade Tampering In India 304
Okian Warrior writes "Hackaday has a fascinating story about Indian college student Debarghya Das: 'The ISC national examination, taken by 65,000 12th graders in India, is vitally important for each student's future: a few points determines which university will accept you and which will reject you. One of [Debraghya]'s friends asked if it was possible to see ISC grades before they were posted. [Debraghya] was able to download the exam records of nearly every student that took the test. Looking at the data, he also found evidence these grades were changed on a massive scale."
Well... (Score:5, Funny)
Sometimes you have to do the needful to get into the school you want.
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It's being done by the tester, not the students, possibly to keep some people (in specific regions) out of the school they want.
It would be interesting to see if the anomalies correspond to cutoff scores for various educational tiers; i.e. if Tier 1 schools require a minimum of say 70 do you see a spike at and after that with a corresponding empty value and or dip just below that. If the anomalies correspond to the cutoff scores for admissions then that would seem to indicate scores were adjusted to help students get in. If you see a spike just before the cutoff and a blank then it may be students were down graded as well.
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It's my understanding that Indian names reflect (or are at least influenced by) the caste and religion of the family. You may not have needed to reveal your caste, you name may have betrayed that information.
Re:Well... (Score:4, Informative)
i believe that was a joke, aimed at the 'indian english'. just sayin' :)
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in jail by the end of the day (Score:5, Insightful)
This would be true in the US and the UK, and India doesn't even match up to those "high" standards. He'll be in jail because someone with power will be embarrassed by this.
Re:in jail by the end of the day (Score:4, Informative)
Good thing he's living in the US then.
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You don't want to go to jail in India.
http://www.clickondetroit.com/news/Novi-murder-suspect-prefers-U-S-jail-to-India-jail/-/1719418/20379814/-/ipn85sz/-/index.html [clickondetroit.com]
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Not that that will save him from getting dragged over the legal coals, just that would be extra embarrassing.
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Probably easily meets the definition of unauthorized access under the CFAA. He's actually guilty of a felony under US law.
Worse, he's whistleblowing, and if there's anything the current DOJ likes to punish worse than hacking, it's whistleblowing.
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not even hacking just URL typing with fixed ID num (Score:2, Informative)
not even hacking just URL typing with fixed ID numbers
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According to my attorney (a former IT person who went to law school), that qualifies as hacking.
He was helping me with a child custody issue, but he had a case where a woman was accused of hacking. He said clearly she couldn't do it as she could barely use a webbrowser and she was accused of a fairly sophisticated attack. He was thinking about using me as an expert witnesss, so we got talking about the subject. He said he'd obviously argue it wasn't if he was the defense attorney, but that case law prese
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Actually it does mean you have permission to do so. It doesn't mean the owners meant to give you permission, however.
That's why you need to be a lawyer to understand this. It's possible that for a given State or Federal law that the owner's intent is what's important, not their implementation. And the intent of the defendant is also a factor.
So, if the owner intended the site to be secure, and the defendant intended to break that security, the actual security might be irrelevant.
IANAL, YMMV, talk to a lawyer in your own state for specifics.
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With typoes and various bugs so prevalent in web server software all over the world, it's unreasonable to postulate malicious intent for changing URLs.
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IANAL, but there are cases being prosecuted for violating Computer Fraud and Abuse Act for "exceeding authorized access".
In the eyes of the prosecutors, "exceeding authorized access" = "unauthorized access" = "hacking".
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Thats right, you use those ad hominems.
Re:not even hacking just URL typing with fixed ID (Score:5, Interesting)
The examples in parent post are wrong.
"Breaking and entering" requires physical trespass. There is no trespass involved when using the GET method, which is part of a standard and open protocol, to request a web page, which in this case is unencrypted and easily read by anyone who asks for it.
The "bait car" analogy fails miserably. There is no property theft involved in what was described by TFA since nobody was deprived of use of anything. In the general case, "intellectual property" is not physical property and courts need to recognize the differences.
If anyone needs a physical analog of what this fellow has done, it is like this:
Imagine that for reasons unknown, the New York City Board of Education recorded the student ids and test scores as graffiti on all the park benches in Central Park. Where any passer-by could read them. Each student was directed to the bench where their data was recorded (in indelible magic marker), and the BoE patted itself on the back for having found a way to make use of all those benches. Then this guy comes along and develops an efficient way to go from bench to bench to bench... Data on the Internet, accessible without any protection to anyone who had or could construct the URL, is as freely available as any graffiti written on a park bench.
Questions should begin with why the India agency responsible for handling this data put up these web pages without involving anyone who had a year or more of training in information management techniques. They certainly had persons on staff who would have avoided making the JavaScript so readily accessible, and there should have been some kind of password scheme so that only the student would be able to access his own scores. Why were their in house experts not involved? It is as if those who were delegated to build the web site did not want to involve anyone who knew enough about data management that they would become suspicious about it being manipulated.
I think there is more than enough evidence here that something is very corrupt in the India education system. Even if the data obtained had not been so obviously altered, the grossly amateur handling of highly personal information stinks to high heaven.
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Re:not even hacking just URL typing with fixed ID (Score:5, Interesting)
If this had happened in the usa
Something very similar to this did happen in the USA, from some time in the 1980s until around 1995. It involved a government forestry agency, and the database they had to track logging, replanting, spraying, road building, and other commercial forest management activities.
I became involved about 1993 when I was hired by an eco-activist group who had used FOIA to obtain a digital copy of a detail report of the entire forestry database for the region. My task was to develop one-off perl scripts to extract the data from the report format and build a Paradox database that could be queried to see if the forestry records indicated any violations of the laws to protect spotted owl habitat. This was straightforward work: as I recall the hardest part was staying awake when doing the validation cross-checking. (I also dislike reconciling my checking account with the bank statement.)
But what I discovered was that the forestry database was full of crap. You cannot harvest a 20 year old stand of timber from a parcel that had been clear cut just three years earlier; you cannot harvest anything from a parcel before the access road to it is completed. A big portion of the database lacked self-consistency. Years later, I learned that the consultant that the forestry agency had hired to develop and maintain the database had been convicted of fraud, and that there had been a shake-up in the management of that agency. (Since the database records were crap, the eco-activists chose not use it in their spotted owl fight. Instead a new, and appropriate, attack on the managerial competency of the forestry agency was launched, I believe by persuading one of the State Representatives to demand an investigation.)
I do not think that computer fraud on this scale is likely to happen in the USA now, because I think every manager of any kind of any large government database is well aware that he needs to cover his ass by having his stuff validated by Information Management. However the news indicates this kind of fraud is happening in some small towns, and some of the smaller departments of cities-- places where there is still no easy access to information management professionals, where decisions involving database management have to be made by persons without a background in the subject.
Re:not even hacking just URL typing with fixed ID (Score:5, Interesting)
Back in late 2009 and early 2010 I was scraping jail inmate registry records for Scott and Dakota County, MN. This was simply a script which incremented the ID numbers by one several times a day and put them out into a CSV. I uploaded these to Google Docs and had Docs Widgets build simple charts based on those data for a rolling ~6 month window of inmates.
As I started looking deeper into the data I started noticing I had ages lower than 18. Odd I thought but sure enough, Scott County was including their juvenile records in the data mixed with the adults even though it wasn't shown on their public website.
I contacted the County and they fixed the bug (you can read about that here: http://www.lazylightning.org/scott-county-quickly-fixes-juvenile-jail-roster-issue [lazylightning.org]) but I was still surprised at the relative lack of security for juvenile records:
It's surprising how lax security is anywhere and to the poster elsewhere in this thread that said this is what you get when you outsource to India, this particular web stuff was not performed with outsourced talent so that comment was nothing short of asinine.
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You're lucky that they responded appropriately by calling you and fixing the problem.
The usual response is to accuse you of being a terrorist/hacker/anarchist/etc. and try to put you in jail.
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Yes, extremely lucky. I wouldn't trifle with law enforcement folks like that. They seem to have a hair trigger sometimes, and not always with their guns. Especially if embarrassed publicly. I'm glad you didn't go to the media. You would likely be in the selfsame list of offenders now, if you had.
Caste system (Score:2, Interesting)
Re:Caste system (Score:4, Interesting)
There is nothing in the article that indicates caste has anything to do with it. Most of the discussion suggested that the cause may have been to "bump" almost-passing grades to passing grades (and presumably other achievement tiers as well).
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It's normal for a test to have a distorted curve, or a bimodal curve, due to any number of factors. True Bell curves only happen in statistically random situations, which testing certainly is not.
However, you should note that scores from 93-100 were almost all possible (curves were smooth) and scores below 30 were also smooth curves. Only the ones in the middle were segmented.
I don't attribute this to malice, but rather some quirk of how they score. Perhaps the score *is* actually just doubled from 50, b
Re:Caste system (Score:5, Interesting)
Technically, in a caste system, you're not allowed to move up except in very narrow circumstances. You're not actually allowed to move at all - up or down. You can be the most brilliant person on the planet, but if you were born to an untouchable in India, well, no one would listen to you.
More likely though, it would be done by people from higher castes because they have a certain image to maintain.
Remember, in Asia, this all derived from the old school British system where exams basically set you on your path through life - basically the final exams at the end of high school was The Final Exam(tm). Score well, and you'd go to university. Score not-so-well, you got to a second-rate college. Score less and you're a lowly tradesperson. Score even worse and you're an unskilled labourer.
So in general, it's an extremely high-stress period where teens would basically be locked in their rooms spending all the time studying because it really is it - no chance to take it over (well, I suppose there are certain humanitarian reasons they allow), and it basically determines your future.
Likewise, for anything with this much pressure on it, people succumb to the human condition - suicide is common, both before and after the exame. Cheating is as well - and many elaborate cheating machines have been conjured up over the years - this isn't your own hide-a-cheat-sheet scale - this is full on tiny 2-way radios and other mechanisms. And of course, hacking of grades to improve one's score.
Interestingly, I think in China one district is forcing all test-takers through a very sensitive metal detector and forcing them to strip - just one step below forcing test-takers to be stark naked during testing. The metal detector is extremely sensitive and basically won't allow anything metal in.
That's how serious the test is, and how serious everyone takes it.
For all its flaws, the modern American system is generally better and more "available" (and even the modern British education system isn't as strict). I'm not entirely sure that letting one test determine your future is entirely wise, and it's one reason why a lot of students travel abroad to study. Some do it because they scored well and got prestigious international study scholarships from their country, but others do it because they couldn't get in, and studying abroad is an option for those that do not pass.
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I don't think it's fair to blame the British for all of that. China has had a stringent civil service exam tradition, for instance, for 1,300 years.
Reddit threw the findings into doubt (Score:2)
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I agree. The distributions are most likely the result of some doubling of actual scores, combined with a small amount of manipulation.
It's clear that there was some rounding-up done near the pass/fail line. It's also clear that there is some extra or different standard of rounding/normalization for those scoring above 90 (or 93).
The fact that they aren't transparent about it is lame, but very Indian.
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Not all his observations. The notable lack of scores leading up to the pass point and the sudden spike at that exact point are particularly notable.
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The thing is, you'll have no odd numbers when you double the values. It's those odd numbers that only occur up in the 90s that stand out--if they are scaling like your theory, then the scorers are screwing with the upper values. If they aren't, they're screwing with the lower values to make those jagged peaks. (And there's still the issue of the missing "just below passing"
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That was a great article.. (Score:5, Insightful)
More for the discussion of statistics than for the really sad excuse for security on those pages..
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You think so?
FTA: Statistics says that if you take enough samples of data, regardless of the distributon, it will average out into a Normal distribution.
News to me.
outsourcing to india (Score:4, Insightful)
this is the type of coding that you get in India stuff done on the cheap and likely to coded to spec with no thinking about how bad of a idea this is.
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Haha. I think he's talking about the government sponsored system to distribute grades to hundreds of thousands of Indian citizens being coded with the primary security being... well obfuscation via JavaScript. Win
Why the Education Board? (Score:2)
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If there was tampering, why is it the assumption of the education board doing the tampering? Maybe other students found this obviously easy "hack" but improved upon the method to actually modify the data.
Two problems with that theory.
1) His "hack" was basically just looking at the JavaScript to learn the public URLs containing each individual's results.
2) The number of students improving upon this (discovering and exploiting the database) to the point of manipulating data would be tens of thousands.
Or just buy degree (Score:5, Interesting)
Nothing I hear about education fraud in India surprises me since one of my Indian coworkers explained how people "buy" degrees from Indian universities.
University employees can be bribed to create the records for an entire curriculum, spanning multiple years of attendance. This record is indistinguishable from a valid one and generates a real diploma. The University will confirm education because "it's in the system".
I think he said it cost about $3000 USD or so for a Masters degree.
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Does that "University" have an on line program? I have a "friend" that would be very appreciative if ... "they" could get a BS degree documented. ....
Massive "scale" is the appropriate term... (Score:2)
I think his results could be explained if the calculation of the final mark in a subject area involve some dodgy math to scale the result such that some intermediate step compresses the possible result to a discrete range of say 50 or so values which are then scaled / normalized to a 0-100 range. This expansion will result in every other final score value being impossible to obtain.
They may be scoring different parts of the exams with different weights, and then combining and scaling the results together, a
that explanation doesn't fly (Score:2)
There are ranges where every integer is represented, other ranges where every other one is missing.
The real smoking gun is that several grades just below a passing grade appear to be promoted up to pass.
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There are ranges where every integer is represented, other ranges where every other one is missing.
The real smoking gun is that several grades just below a passing grade appear to be promoted up to pass.
If you recognize that your evaluation system only has an accuracy of +/- 3% it does make some sense to bump up those below the passing grade by that much to the level of the passing grade. It also saves a whole lot of resources by not having to field requests for regrades and reevaluations from all of those students who are just barely below the cutoff.
When your tools are imperfect (and they all are), there is no absolutely "fair" way of dividing a large group into two mutually exclusive categories. You mig
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Actually, given the consistent spiking at specific grades on the ISC and ICSE charts, there may be some significant "grace" marking going on, and not just at the pass mark, I'm talking larger than normal shifts between valid marks (around the 70's and 90's). Both the ISC and ICSE tests are 40 questions on every subject, so there shouldn't be any marks at 96, 98 and 99 too, yet those graphs suggest that some students did get those marks.
Wont jump to conclusions. (Score:2)
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Education in India (Score:5, Informative)
What does "ls -l" do? Please describe below.
That kind of thing. So, I'm not surprised if institutions are manipulating test scores. India is more about the perception of computer savvy developers than the reality of it.
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i think he's mostly wrong! (Score:2)
the thing he seems most concerned about are that out of 200,000 or so students, there are many marks that were not received, especially in the middle sections of the grades. values like 81, 83, 85, etc. were earned by zero students while values like 80, 82, 84 were received by tons.
this seems absurdly easy to explain.
say students are graded on a 50-point scale, which is then doubled (eliminating half of all possible values), and then some kind of curve is applied, which bends some values into other-wise una
Finally... (Score:2, Informative)
Some basic problems with this story (Score:2, Insightful)
"Hacked" means "retrieved from a web server in the way they were intended to be retrieved." The fact the webserver was completely unsecured is, however, worrying.
"Widespread grade tampering" means "statistical evidence that the final grades are not the raw grades, but have been adjusted according to some system as yet unidentified." The nature of the adjustment is as yet unidentified - it could be nefarious, or is much more likely to be according to policy. Pretty much every school system in existence do
Re:Some basic problems with this story (Score:5, Informative)
Re:Some basic problems with this story (Score:4, Interesting)
I've read the original. Whether your policy can produce that sort of distribution depends entirely on what the policy is, no?
As an example of a system that produces exactly this sort of pattern, at my university the pass grade was 50%. Anyone who scored at least 45% but less than 50% in the exam could apply to sit a supplementary exam a few weeks later. The supplementary exam score would then be your final score, but the maximum mark available in the supplementary exam is 50%. If this results in you scoring 50% then the subject is recorded as a "conceded pass". You can only take one conceded pass in a year and many degree programs also limit how many conceded passes you can count towards your degree.
It's a system that lets you have another go if you had a bad day in an exam and, yes, in many subjects it produces this pattern of no-one receiving 45, 46, 47, 48 or 49 and a big lump of people receiving 50.
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There's nothing like that in the system in question though in anything discussed publicly as far as I can tell. although your basic point is a sound one. Note that if you had a very large system, like say your university system but done in a hundred schools then you'd expect to see still a few people in the 45-49 range. But you are correct, there could be some issue like that, but if so, no one has identified it yet. But you are correct that this sort of thing can happen, and your point makes me update in
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From his article:
And then an addendum in response to an article:
Re:Some basic problems with this story (Score:5, Interesting)
The criticism seems rather pedantic. I'm the last one to defend the barely-reading, never-correcting, link-to-blog-post-instead-of-actual-article, duplicate-posting slasheditors, but the fact is:
1) the server has a place where you put in a code and, i'd guess, a passcode. He looked at the code, determined the data was being drawn by a simple java query to an unsecured text file. Did he get the data the way it was intended? CERTAINLY not. Did he essentially 'break in' through what was relatively tissue-thin (derived from obscurity only, really) security? Yes, I'd say he did. So yes, in MOST people's definitions, he 'hacked' their shitty website.
2) WTF are you talking about? Every school system in existence ADJUSTS grades on standardized tests? Proof? The guy discovered that something like of the passing scores (everything > 35), like 40% of the possible scores NEVER showed up. Ie, nobody *ever* got a score of 82, 84, 91, or 93, while 94-100 was regularly distributed. Mathematical anomaly? Maybe. But that seems unlikely with a massive test, and multiple added scores that this is possible.
I think what he discovered was a ridiculously insecure web service, and a list of grade scores that have suspiciously regular omissions.
So "hacked" and "possible grade tampering" seems pretty spot on.
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No.
1, there was no passcode. He retrieved the data in exactly the way it was intended, just on a much larger scale than was intended.
2, "Every school system" is perhaps an exaggeration, but many education systems do deliberately manipulate scores to fit a distribution. It's justified in various ways. For instance, suppose that in one particular year the physics exam was unusually difficult. That would disadvantage everyone who took physics compared to everyone else. So you might choose to redistribute
Why is this surprising? (Score:5, Informative)
1. Teachers have to ensure that their class marks have a certain average and median before they submit them. There can't be too many failures either.
2. Teachers know not to give a grade of 49 if the pass is 50 since the student will argue to get that missing point. If you want to be safer, just don't give out anything in the forties.
3. If a test gives letter grades, that equates to a particular number. A = 85, A- = 83, and so on. In that case, no one gets an 84, ever.
What!? (Score:2)
Facts be damned (Score:2)
1. Kid figures out query params and post fileds in http
2. Kid mines data from a public web server to get publicly available information.
3. Kid "analyzes" data statiscally, finds a pattern to grading
4. Kid dubs it tampering. (Tampering would be if the evaluators grading were to be replaced with something else. )
5. Tech dumb media latches onto the story, makes a celebrity out of a kid scraping data off a website.
6. Education agency is pissed off for really no fault of
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"Kid gets arrested when he land in India in the summer vacation"
Doesn't even need to. Indian Police Service refers the case to Interpol, where it will contact the US Department of Justice to issue a federal arrest warrant and extradition request on him for "hacking across state lines"
I reached a different conclusion (Score:3)
My conclusion was that they rounded the grades to certain points. I'm not sure where he got the inference of malice or tampering, other than bumping failing grades up, which isn't exactly malicious (though probably unfair).
Never attribute to malice that which can be explained by stupidity... or policy.
Also, I give this guy a couple of days, a week max, before he's in jail for quite a while.
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Have you seen the curves? They don't even approach a poisson distribution.
Re:and how many people just cramed the test (Score:4, Insightful)
Are you trying to mock educational standards by pretending to be someone who failed statistics?
Poisson distributions have to do with frequency of repeatable events over time. You meant Gaussian or Normal distribution.
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Re:and how many people just cramed the test (Score:4, Informative)
Correct; typical example could come from counting, then plotting, discrete data. Number of children in a family, doors on a car...
Note that whilst you might expect a normal distribution, with events (exam results) distributed evenly but randomly about the mean, the fact the the guy found something that certainly looks non-normal, (he did not do normality tests, but having looked at his results, I don't think he needed to), does not itself prove that the results were altered.
Imagine a 'perfect' exam, where the expected (average) result for the student population was 50 out of 100, or 50%
Now imagine an (equally unlikely) 'perfect' candidate population.
If you plotted the exam results, you could expect the population to be centered on a mean result of 50, with half the scores higher, half lower.
If you had a (really getting unlikely now) 'perfect' education system, there would be a low standard deviation in your data, let's say 2%
If the results could be modelled with the Gauss curve, then 99.73% of your distribution would be at +/- 3 sigma (standard deviations) from the mean.
So lowest expected score of 50-2*3=46, with highest of 56.
Of course, candidate abilities could be much more varied than this, so sigma could be anything...5%, 10%
Anyway, getting to the point, if the mean of a what you *might* be expecting to be a Gauss / Normal curve is shifted sufficiently towards a 'hard' limit, (in our example, you cannot score less than 0%, or more than 100%, so both are 'hard' limits, or 'boundaries'), then the data (example results) do tend naturally to 'pile up' against the limit. (Think of a snow plough pushing snow aganist a wall - it's go nowhere to go, except up).
Thus you get a non-normal distribution, (typically better modelled with a lognormal or Weibull curve, not Poisson).
But WHAT can cause the mean to shift? For this example:
- Either the exam is "too easy", or
- The students are all very good (yeah, same thing,really), or
- The marking system is biased.
I'll leave you to draw your own conclusions on that one, but I've personally found that in India, (as in other places, including the USA), a little cash can go a long way...
But that was not the most compelling evidence of bias; that would be the very strange 'missing' data points, (especially close to critical scores such as the 35 pass. /endoldstatsbore
The Author is an Idiot (Score:5, Insightful)
Possibilities:
- There is a national cheating conspiracy ...or....
- The test score is not based on assigning a value to each question and adding up those values.
For example, the test could simply be scored as such:
All answers correct: Score 100
Miss one question: Score 99
Miss two questions: 98
Three questions: 97
Four: 96
Five: 94
Six: 92
etc etc
Miss 20 questions: 35
Miss 21 questions: 31
etc etc.
The author makes the ASSUMPTION that the score of the test must be the sum of the value of the questions answered correctly. There is no basis for that assumption. The fact that certain values are not present, and the values 34, 33 and 32 are not present, are likely by design (i.e. don't make people feel like they just missed passing.)
All the author has shown is that India is apparently doing a very poor job teaching critical thinking skills (as evidenced by the author's inability to exercise critical thinking skills.)
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The author fails to take some things into account however, and Im not totally convinced because of the holes in his reasoning. For example:
One of the most common critiques of my theory was this - maybe there were questions with only 3 or 4 mark intervals in all subjects making certain marks mathematically unattainable. My counterargument? All numbers from 94 to 100 are attainable and have been attained. What does this mean? It means that increments of 1 to 6 are attainable. By extension, all numbers from 0 to 100 are achievable.... If 99 and 98 were definitely achievable with deductions of 1 and 2 respectively, this means one of two cases - there is a question A worth 1 mark that made 99 occur, and a question B worth 2 maks that made 98 occur, which meant getting A and B both wrong would mean 97 could occur.
Unless, of course, there are 2 1-point questions on the test, and all the rest are 4-point questions, in which case a 99, 98, and 96 would be attainable, but 97 would not. Perhaps the majority of questions were multi-part, worth multiple points, and getting a part wrong meant getting the whole wrong.
It definately looks wierd and he may be on to something, but you cant
Re:and how many people just cramed the test (Score:5, Informative)
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Without knowing how many questions are given in each section, and how they're scored, that's not possible to say. The set of possible scores doesn't necessarily include every value from 1-100.
If there are 30 questions in a section, and it's scored on a straight percentage basis, you're going to see discrete peaks every 3.33%, and nothing in between. Gosh, just like on the graphs.
That doesn't explain the odd overall distributions, however.
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Re:and how many people just cramed the test (Score:4, Informative)
Re:and how many people just cramed the test (Score:5, Insightful)
Why don't you just read the fucking article instead of trying to come up with your own wackjob explanation? He quite clearly explains it:
One of the most common critiques of my theory was this - maybe there were questions with only 3 or 4 mark intervals in all subjects making certain marks mathematically unattainable. My counterargument? All numbers from 94 to 100 are attainable and have been attained. What does this mean? It means that increments of 1 to 6 are attainable. By extension, all numbers from 0 to 100 are achievable.
Let me give you an example. If 99 and 98 were definitely achievable with deductions of 1 and 2 respectively, this means one of two cases - there is a question A worth 1 mark that made 99 occur, and a question B worth 2 maks that made 98 occur, which meant getting A and B both wrong would mean 97 could occur. Case 2 - Question A was worth 1 mark, and question B was worth 1 mark too. The 99 got A wrong, and the 98 got A and B wrong. By this logic, if 97 were not possible, it would mean that there is no other question of 1 mark in the examination or that nobody got a 2 point question wrong and question A or B.
Basically, because 99, 98 and 97 were all attained, then any increment of 1, 2 or 3 points should be possible. The fact that nobody got 80% in any subject in the entire country points to widespread tampering.
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Kinda like yours, except that you likely know even less about the test than he does.
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Such a test would resemble dumb Facebook games:
Achievement unlocked: clicked mouse.
Achievement unlocked: typed your name.
BONUS Achievement unlocked: +5 points. Buy more with your credit card!
Comment removed (Score:5, Informative)
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The author answers your objections. First, the missing values didn't have consistent intervals (it wasn't always every 3 points). Second, the grades from 32 to 34 didn't appear in the data. That gap seems unusual. Third, there weren't gaps from 94% to 100%, so it's known to be possible to attain percentages that aren't divisible by three, for example.
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Unless it's not grade data but raw data. Everyone is ASSUMING it's final calculated scores.
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There are fragments on the curve with no missing integer values. The marks for the individual questions themselves are docile - there's no reason NO ONE would get a particular score, other than tampering. The dips you see in the curves are ZEROES. As in not a single person getting such mark.
Plus, this just doesn't make sense (Score:3)
So let's say that some numbers are "missing." Why would someone manipulate the exact same numbers to be missing across all of the exams? I mean, I could see bumping a 32, 33, or 34 (non-passing) up to a 35 to have pity on some poor schmuck who came really close to passing, but why would, say, someone change a 93? I mean, not just for one student, but all the way across the board? What possible motivation could someone have to say "That's got to be either a 92 or a 94, we can't have any 93s"?
I'm inclined
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You need to read TFA http://deedy.quora.com/Hacking-into-the-Indian-Education-System [quora.com] that should give you an idea of what the person in the article talks about with tampering data. Even with 1 question asked in the test, the score range should not be this ugly or the evaluation/grading method is not up to par. TLDR summary, it is statistically impossible to miss that "many" score points between 1~100 from this size of data.
On a side note, I am not sure whether the person is going to jail... I hope there won
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He's at Cornell University, that doesn't discount the possibility of jail time but it does pretty much eliminate the rendition aspect (he didn't piss of the US government afterall).
ok everyone just go read the article (Score:2)
"There are missing scores (from 1-100) "
Without knowing how many questions are given in each section, and how they're scored, that's not possible to say. The set of possible scores doesn't necessarily include every value from 1-100.
If there are 30 questions in a section, and it's scored on a straight percentage basis, you're going to see discrete peaks every 3.33%, and nothing in between. Gosh, just like on the graphs.
That doesn't explain the odd overall distributions, however.
94-100 or so were attainable. there's an entire paragraph devoted to how it can't be that the questions had such a scoring system which made certain numbers unattainable.
scores leading to the cut off point at bottom end were not attainable. the tampering is that everyone under a certain score by certain amount were upgraded to the passing grade.
now there wouldn't be a problem if the passing grade was supposed to be -4 of what it is. the baffling thing is that it seems that EVERY FUCKING AUDITOR in the syste
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Of course there is a perfectly reasonable explanation for it: The grades are deliberately manipulated to fit some preconceived distribution. Lots of school systems do it very openly. The only surprising there here is that either the school system didn't disclose that they do it or that some idiot wrote an article without checking first. I don't know which: TL;DR.
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The problem he pointed out is that there are parts of every graph where the non-multiple case applies. This refutes the "every score is a multiple" theory, unless multiplication was not the final step. If there is a step after multiplication, how are bonus points awarded?
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The US has never been high on education.
At least from K-12, College Education in the US is rated quite high though.
If you have ever worked with a lot of these students from non-US background. You find that they are quite booked learned, however tend not to be very good in the practical matters of actual work.
For example in Computer Science, it is good to know how Big O works and how memory allocation, and following an object oriented structure works. However you need practice to know when and how to use th
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yup. there does seem to be some evidence of grace scores down near the passing level, and it'd be interesting to theorize about the bimodal distribution he's seeing in places, but the jagged graphs are what he seems to be most concerned about, which are most likely simply a product of how the test was weighted or curved or whatever.
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oh please, people have been stuffing ballot boxes since voting was invented. computer systems aren't inherently any less secure than analog ones. go live in a shack in the woods if you hate progress so much.
parent is racist (Score:2)
ick.
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racism makes your day? cool bro.