error bars eXXXcel

[-]

how do I add error bars going in the vertical direction because I can only do it in the horizontal?

also, anyone know of any science competitions where you submit a report to them (like a science report)?

[luken93]

what version of office are you using?

[-]

07

[/0]

On your graph (XY scatter is usually best for your generic line of best fit graphs), right click on a particular data point, and select "Format Data Series", then there are tabs that say "X error bars" and "Y error bars". Click on those to edit horizontal and vertical error bars respectively.
Unfortunately with Excel you can't have error bars that are more complicated functions of x and y. You will need programs like Mathematica to do this (or you can draw them in paint).