5 ms·

I agree. Most campuses use a product called Turnitin, which was originally designed to check for plagiarism. Now they claim it can detect AI-generated content w

by vondur 11mo ago

I agree. Most campuses use a product called Turnitin, which was originally designed to check for plagiarism. Now they claim it can detect AI-generated content with about 80% accuracy, but I don’t think anyone here believes that.

phh 11mo ago
80% is catastrophic though. In a classroom of 30 all honest pupils, 6 will get a 0 mark because the software says its AI?
- v9v 11mo ago
  I suppose 80% means you don't give them a 0 mark because the software says it's AI, you only do so if you have other evidence reinforcing the possibility.
  - respondo2134 11mo ago
    no, you multiply their result by .8 to account for the "uncertainty"! /s
- yoavm 11mo ago
  The promise (not saying that it works) is probably that 20% of people who cheated will not get caught. Not that 20% of the work marked as AI is actually written by humans.
- CaptainNegative 11mo ago
  It depends on their test dataset. If the test set was written 80% by AI and 20% by humans, a tool that labels every essay as AI-written would have a reported accuracy of 80%. That's why other metrics such as specificity and sensitivity (among many others) are commonly reported as well. Just speaking in general here -- I don't know what specific phrasing TurnItIn uses.
- j45 11mo ago
  I think it means every time AI is used, it will detect it 80% of the time. Not that 20% of the class will marked as using AI.
  - respondo2134 11mo ago
    you're missing out on the false positives though; catching 80% of cheaters might be acceptable but 20% false positives (not the same thing as 20% of the class) would not be acceptable. AI generated content and plagarism are completely different detection problems.
    - j45 11mo ago
      For sure. False positives with technology that is non-deterministic is guaranteed. It's more than slightly comedic people being amazed when LLM math works as it's created to.
- kelseyfrog 11mo ago
  80% accuracy could mean 0 false negatives and 20% false positives. My point is that accuracy is a terrible metric here and sensitivity, specificity tell us much more relevant information to the task at hand. In that formulation, a specificity < 1 is going to have false positives and it isn't fair to those students to have to prove their innocence.
  - soVeryTired 11mo ago
    That's more like the false positive rate and false negative rate. If we're being literal, accuracy is (number correct guesses) / (total number of guesses). Maybe the folks at turnitin don't actually mean 'accuracy', but if they're selling an AI/ML product they should at least know their metrics.
tyleo 11mo ago
I had Turn It In mark my work as plagiarism some years ago and I had to fight for it. It was clear the teacher wasn’t doing their job and blindly following the tool. What happened is that I did a Q&A worksheet but in each section of my report I reiterated the question in italics before answering it. The reiterated questions of course came up as 100% plagiarism because they were just copied from the worksheet.
- pirates 11mo ago
  This matches my experience pretty well. My high school was using it 15 years ago and it was a spotty, inconsistent morass even back then. Our papers were turned in over the course of the semester, and late into the year you’d get flagged for “plagiarizing” your own earlier paper.
  - SoftTalker 11mo ago
    > you’d get flagged for “plagiarizing” your own earlier paper Wow I'd have been screwed, so many of my high school papers were just rewrites and improvements on stuff I wrote in earlier years.
- teaearlgraycold 11mo ago
  Funny how it's the teachers that are plagiarizing the work of the tools.
vkou 11mo ago
> but I don’t think anyone here believes that. All it takes is one moron with power and a poor understanding of statistics.
jimbob45 11mo ago
Had a professor use this but it was student-led. We had to run it through ourselves and change our stuff enough to get a high enough mark to pass TurnItIn. Avoided the false allegations problems at least.
ball_of_lint 11mo ago
I have had Turnitin flag my work as plagiarism for quotes from the relevant text that were quite clearly indicated as quotes. It's shit software for schools and teachers to cover their ass. Nothing more, and deserves no more attention.
seanw265 11mo ago
If they are serious they should realize that "80% accuracy" is almost meaningless for this kind of classifier. They should publish a confusion matrix if they haven't already.

by vondur 11mo ago

phh 11mo ago

80% is catastrophic though. In a classroom of 30 all honest pupils, 6 will get a 0 mark because the software says its AI?

v9v 11mo ago
I suppose 80% means you don't give them a 0 mark because the software says it's AI, you only do so if you have other evidence reinforcing the possibility.
- respondo2134 11mo ago
  no, you multiply their result by .8 to account for the "uncertainty"! /s
yoavm 11mo ago
The promise (not saying that it works) is probably that 20% of people who cheated will not get caught. Not that 20% of the work marked as AI is actually written by humans.
CaptainNegative 11mo ago
It depends on their test dataset. If the test set was written 80% by AI and 20% by humans, a tool that labels every essay as AI-written would have a reported accuracy of 80%. That's why other metrics such as specificity and sensitivity (among many others) are commonly reported as well. Just speaking in general here -- I don't know what specific phrasing TurnItIn uses.
j45 11mo ago
I think it means every time AI is used, it will detect it 80% of the time. Not that 20% of the class will marked as using AI.
- respondo2134 11mo ago
  you're missing out on the false positives though; catching 80% of cheaters might be acceptable but 20% false positives (not the same thing as 20% of the class) would not be acceptable. AI generated content and plagarism are completely different detection problems.
  - j45 11mo ago
    For sure. False positives with technology that is non-deterministic is guaranteed. It's more than slightly comedic people being amazed when LLM math works as it's created to.
kelseyfrog 11mo ago
80% accuracy could mean 0 false negatives and 20% false positives. My point is that accuracy is a terrible metric here and sensitivity, specificity tell us much more relevant information to the task at hand. In that formulation, a specificity < 1 is going to have false positives and it isn't fair to those students to have to prove their innocence.
- soVeryTired 11mo ago
  That's more like the false positive rate and false negative rate. If we're being literal, accuracy is (number correct guesses) / (total number of guesses). Maybe the folks at turnitin don't actually mean 'accuracy', but if they're selling an AI/ML product they should at least know their metrics.

tyleo 11mo ago

I had Turn It In mark my work as plagiarism some years ago and I had to fight for it. It was clear the teacher wasn’t doing their job and blindly following the tool. What happened is that I did a Q&A worksheet but in each section of my report I reiterated the question in italics before answering it. The reiterated questions of course came up as 100% plagiarism because they were just copied from the worksheet.

pirates 11mo ago
This matches my experience pretty well. My high school was using it 15 years ago and it was a spotty, inconsistent morass even back then. Our papers were turned in over the course of the semester, and late into the year you’d get flagged for “plagiarizing” your own earlier paper.
- SoftTalker 11mo ago
  > you’d get flagged for “plagiarizing” your own earlier paper Wow I'd have been screwed, so many of my high school papers were just rewrites and improvements on stuff I wrote in earlier years.
teaearlgraycold 11mo ago
Funny how it's the teachers that are plagiarizing the work of the tools.

vkou 11mo ago

> but I don’t think anyone here believes that. All it takes is one moron with power and a poor understanding of statistics.

jimbob45 11mo ago

Had a professor use this but it was student-led. We had to run it through ourselves and change our stuff enough to get a high enough mark to pass TurnItIn. Avoided the false allegations problems at least.

ball_of_lint 11mo ago

I have had Turnitin flag my work as plagiarism for quotes from the relevant text that were quite clearly indicated as quotes. It's shit software for schools and teachers to cover their ass. Nothing more, and deserves no more attention.

seanw265 11mo ago

If they are serious they should realize that "80% accuracy" is almost meaningless for this kind of classifier. They should publish a confusion matrix if they haven't already.