"This data was gathered on an internet forum on which it is possible for a single person to create multiple accounts (and therefore vote multiple times) as well as for bots to register and vote.

If you put it somewhere like the backroom then there is a very limited possibility of that... though a member with multiple accounts could vote twice, anyone who has two active accounts probably uses them for a much better reason then screwing with jobs linking to paticular foods polls....

It is also impossible to know if the information given is accurate or not, or if the people are really who they say they are.

Probably the best criticism of the method, there would be very little reason to lie on the what foods you like, the only reason to lie would be for pure fun... so most would probably give honest answers...

The profession one there is an excuse to lie, make yourself look good, why be a binman when you can be a lawyer, my counter point though is that, we have a fairly mature community so lieing is slightly less likely... alot of people who do work crap jobs are proud that they work so hard... and lastly alot of .org members who have been here a bit will have likely dropped hints or outright told people what thier occupation is, so would not be eager to potentially be branded a liar...

It might also be pointed out that you would be drawing false conclusions from your data - there is no reason to believe that your job determines the food you like.

Going to have to disagree here, atheletes are attracted to healthy food, so would probably come out as having preferences for healthy foods, if we further specify atheletes are likely to eat certain foods depending on thier sport, a wieght lifter and a marathon runner, the weight lifter would have similar diet preferences to other wieght lifters... but probably a little different to the marathon runner... whose diet is much more similar to the other marathon runners...

Then we could get onto people with busy hectic jobs with long hours having preferences for fast easy food... ect.