Finding out if the work of a student is a copy of of the work of another one

francois_boulet

Is there a better way than going in "Versions & history" and clicking a hundred time on "Show more changes"  ???
Someone found a way ?

NeilCooke

Click on “Start” in the Versions and History. If it shows geometry it was copied.

francois_boulet

But you can't see from who it comes.
I'm I wrong ?

NeilCooke

No you can’t but you can disqualify the student who submits it. 

brian_brady

I also generally disqualify the student who shared their work.

francois_boulet

Thanks Neil

john_mcclary

How can you tell if they shared? If they removed the share before submitting. Or duplicated a doc and shared that? 

What if someone shared with them so they could help someone work through a problem through collaboration tools?

justin_36

Like with any cheating scenario, there's always a possibility of getting around it: a student could share credentials with another to "do the work" for them under a different username.

Still, I am very glad for Onshape both the cloud-based and seeing the history of when kids are doing their work, the majority of whom will do their work in a fair manner.

In other instances, I have asked a questionable student to explain the process of making the file, maybe not click-by-click, but talking through, as if they are teaching. They could use a presentation (screenshots) or whatever thing short of having them actually show you them doing Onshape. Usually this can tease out whether or not they know their stuff and if it is a red flag, hopefully it can be addressed more at the root cause (lack of confidence, other stuff going on in life, etc.). This type of diagnosing becomes harder and more important in a time of distance learning.

david_kurtz

I'm glad to see that I'm not the only one with this question. I'm new to teaching my class with Onshape, so this is a learning process for me.

I came across this situation. This screen shot is all I see in the history for a student project.  There should be a sketch and a revolve.  It would be nice if the history said that a copied sketch or feature was inserted, preferably with a mention of the parent file (even if this said 'document no longer shared/available').  
  

NeilCooke

@david_kurtz - that screenshot shows that the document was copied from someone else and no work has been done in that document since it was copied - therefore that student has not done any work on the project other than copy it from someone else.

david_kurtz

@NeilCooke Thank you for the quick reply.  I am able to do some forensic work and am pretty sure were their copy came from.  I appreciate Onshape showing the number of copies made.

jack_aiello

Hi, It would be helpful for me to see a side by side comparison of screenshots between the two version histories, someone with original work, and then compare it to someone who made a copy of someone else's work changed the name and then submitted it.  Can you please post a comparison example so I can see the difference?

One thing that I do to slow down the amount of direct copying and renaming of files is that I try to create differences or variations in assignments within a class. Students can't do a wholesale job of copying each other's work and submitting it without being in the same group.  They might be able to copy the assignment from someone else in their group, but not a wild copy of just anyone else's work since the features or dimensions would not be the same as the rest of the class. 

Domenico_D

@jack_aiello Here are two screenshots of the history from a project that I was working on. The original is the document that I was actually working on and the copy is just that. As you can see, when you make a copy, the previous history from the original is not transferred to the copy. If a student's work has no changes in the history, then it had to be copied from somewhere. 

As @NeilCooke pointed out, you can also click on Start in the history to see the student's start point. If there is any geometry present at the start, then that geometry was copied from somewhere. If a student edits a copy to make it look different than the original or to make the history look full, checking start will let you know that there was initial geometry copied from somewhere. 

NeilCooke

Thanks @Domenico_D

francois_boulet

Our evaluation policy try to discourage both the source and the cheater.
It would be very useful, when you click ''Start'', to see the source document's name and author.
This traceability would also be useful in other field than education.
I logged an I.R. for that, named:
''Traceability for copied documents''

mcheli_academic

francois_boulet said:

Our evaluation policy try to discourage both the source and the cheater.
It would be very useful, when you click ''Start'', to see the source document's name and author.
This traceability would also be useful in other field than education.
I logged an I.R. for that, named:
''Traceability for copied documents''

Love this idea!

PAH

I just look at a sketch and compare. You can see these students copied just by the location of the dimensions.

Matthew_Curran

In addition to checking the versions and history to verify that a part studio was copied. The code generating a part studio can be checked and compared to the code generating other part studios, using a text comparison tool such as diffchecker, to help verify where the part studio was copied from. 

To check the code for a part studio, right click on the part studio tab at the bottom and select “Show code” this will add and open a tab on the right-hand side of the screen showing the code.  

I did some quick testing and found that the ids for sketch elements are the same between an original part studio and the copied version, while a part studio modeled separately with identical techniques to the original will result in different ids being produced. I created a simple model with a sketch, extrude, and chamfer feature, and the text comparison tool I used showed only 29 differences between the original and the copy, and 128 differences between the two models created using the same techniques. 

Doing this manually can be tedious to cross check models created by a large group of students, but I think this could be helpful to verify the original part studio after using techniques that others above have mentioned.  

Something that I’m sure would take a lot of effort but could be a really nice feature of the education enterprise plan would be something similar to Turnitin, where an educator could setup an assignment that students would submit their documents to, and each part studios code could be cross referenced to find and flag any part studios with a low level of differences.  

nick_papageorge073

Dumb question from someone 20some years out of college: Are these high school or college kids that are cheating? Or both? Don't they like the class? I found the engineering class in high school to be one of my favorites. In college, the CAD class was considered fun and easy as heck in the engineering curriculum, especially compared to the calculus classes. I'm surprised people would cheat on CAD assignments. What do they expect to do once they become engineers? Or are the cheating kids not going down that path?

julie_kiel

Matthew_Curran said:

In addition to checking the versions and history to verify that a part studio was copied. The code generating a part studio can be checked and compared to the code generating other part studios, using a text comparison tool such as diffchecker, to help verify where the part studio was copied from. 

To check the code for a part studio, right click on the part studio tab at the bottom and select “Show code” this will add and open a tab on the right-hand side of the screen showing the code.  

I did some quick testing and found that the ids for sketch elements are the same between an original part studio and the copied version, while a part studio modeled separately with identical techniques to the original will result in different ids being produced. I created a simple model with a sketch, extrude, and chamfer feature, and the text comparison tool I used showed only 29 differences between the original and the copy, and 128 differences between the two models created using the same techniques. 

Doing this manually can be tedious to cross check models created by a large group of students, but I think this could be helpful to verify the original part studio after using techniques that others above have mentioned.  

Something that I’m sure would take a lot of effort but could be a really nice feature of the education enterprise plan would be something similar to Turnitin, where an educator could setup an assignment that students would submit their documents to, and each part studios code could be cross referenced to find and flag any part studios with a low level of differences.  

I think one of my students has used someone else's cad, brought it into onshape, but with history.  I wonder if he copied the code, then replaced his name.  There were a ridiculous number of hours, mostly over night, and the model is very sophisticated in the way it was constructed.  He is a beginner.  Any ideas on if this is possible?

dirk_van_der_vaart

Maybe he copied the method how to construct a proper model, that's also studying.
Maybe he did a lot trial and error on other document's before he started with the final document, that's also studying.

Matthew_Curran

julie_kiel said:

I think one of my students has used someone else's cad, brought it into onshape, but with history.  I wonder if he copied the code, then replaced his name.  There were a ridiculous number of hours, mostly over night, and the model is very sophisticated in the way it was constructed.  He is a beginner.  Any ideas on if this is possible?

My understanding is that it's not possible to copy code from one part studio and directly paste it into another to generate features and geometry. 

john_mcclary

just checking the Start position of the document should be enough to tell you if it was copied.

now with history search, you can set it to be all the changes that happened in the first few hours and see how it started out

julie_kiel

He made a Starwars AT-AT Walker.  

I hope he studied a video and made it, I would be fine with that.  He said he did not watch a video and he doesn't know how he got his dimensions.  He claimed to have made it himself.  The history shows many, many hours - midnight to 7AM some days, 12 hours at a time over several days.  More than 2600 changes.  Multiple complex parts into an assembly.  He was home with covid for a week +.  It sounds like everyone here is pretty convinced there's no way to hack the history.

john_mcclary

Sounds like he had a lot of spare time. Would he be willing to share it with the community? I mean, when I was in high school midnight to 6am was where I learned to code...  i just slept through math class of all places 

caroline_koenig

Hello John M,
Do these start and end dates need to be put in by the user OR is it automatic? My files do not show the dates as your image shows above- mine are blank. Thank you very much.

john_mcclary

you can fill them in manually or use the calendar picker on the right side.

I just opened the history and looked at the start time of my document, then just filled in a range of dates.

search history is a brand new feature, you can learn about it by watching the first video here:
Improvements to Onshape - January 12th, 2022 — Onshape

caroline_koenig

Thank you for your reply John- it would be great if Onshape just filled this in automatically when a document is created- then students could skip this step..many students forget or skip the steps for submitting/sharing files. 
Thank you for the resource!

john_mcclary

this isn't a step done by the student. It is a history search tool filled in by the teacher or whoever is investigating the document for cheating.