I've noticed recently that some really poor questions are being asked by users with usernames that consist of two lowercase characters followed by four digits. For example, here's one from user gc7283: current amplification and filtering circuit project proteus

A quick search for unique text reveals that this question comes almost verbatim from a question on Chegg, which is a well-known and much-despised for-profit homework/quiz cheating service: Question: A Remote Motor Speed Sensor Provides A Current Signal....

Is the default format for new usernames just two lowercase characters and four digits? Could it be that a bot is copying these questions from Chegg, or are we looking at a real person trying to make a quick buck by selling our answers?

EDIT: Here is an example of one of the "4-wire fan" questions: IS this the correct way to control the speed of a 4 wire CPU fan? This user just had one lowercase letter followed by four digits. I guess the MO has changed a little.


2 Answers 2


I think those are real users with genuine questions.

I didn't find any other examples than the ones you gave, and that user even took time to create a circuit in our specific circuit lab. It is highly unlikely that a bot did that. I think it is more likely that a genuine user posted the question both here and on Chegg.

The second user you found still remaining on the site also took the time to create a circuit specifically for this website, something a bot could never have done. They also interacted with other users in the comment section, applied the advice and reported back with the result. Finally, I couldn't find the question on Chegg when searching (and what kind of exam involves retrofitting a PC fan anyway?).

  • \$\begingroup\$ There have been several questions lately about controlling a 4-wire computer fan for temperature control, using PWM or a thermistor. It seems that these users are deleting their accounts after asking just a few questions. \$\endgroup\$ May 2, 2021 at 11:51
  • \$\begingroup\$ @ElliotAlderson Ok, I went through the last seven days of new accounts, and found none matching the description. If the user deletes the accounts that could explain it. \$\endgroup\$
    – pipe
    May 2, 2021 at 11:54

If someone did copy an answer or question from SE that's fine, but (I would think) they need to also provide a source link to the question and provide attribution of the CC license (all material is released on the CC license on SE and the license needs to be followed).

I don't think I'd really worry about this too much, unless there is a lot of this activity going on and someone is copying questions in bulk without attribution. If someone is doing bulk copying then that would definitely be a red flag.

However it is annoying if people are deleting and recreating accounts, if you see that kind of activity (and it looks like it's related to the same user), if you could get a username (or user number) and forward that info to the moderation team then we could look at that activity.


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