Need some help with graphs.

[samoward]

Hi, I never really use excel, nor am I any good at it so this question may be seem stupid to many of you.

Basically for a school project, I had to make a questionnaire and retrieve data and then plot it in excel, I'm trying to find out if internet speeds at a student's house affects how much schoolwork they do at home.

I;m trying to present some data using graphs but mt complete lack of knowledge in excel isn't helping.

To put it shortly, two of my questions are 'How fast is your internet speed at home?' (with 8 options ranging from 'very poor' to 'excellent') and 'how much time do you spend on schoolwork at home each day?' (again with 8 options of time periods, i.e. '15-30 minutes', '1-1 and a half hours'). I am looking to create a scatter graph to see if there is a correlation between the two values, with internet speeds running along the X axis and study time up the Y. I am not sure which pieces of data to include to create the scatter graph, and am stuck.

I have the amount of people for both internet speeds as well as study time but am really confused. I am finding it hard to word my problem so all help will be appreciated.

Thanks! Sam.

 

[xenou]

I think you have to make the data quantitative in order to use an x-y graph. Internet speeds could be numeric from 1 to 8, with 1 as very poor and 8 as very good (or vice versa). Time studying is already numeric (if necessary use the midpoint of each bucket as the value -- i.e, [1 - 1.5 hours] could be valued at 1.25).


Another way (which isn't correlation, however) would be to graph the amount of time spent study as the "X-axis" and the average internet speed as the "Y-axis". Or vice versa: average internet speed as 8 points on the X-axis, and the average time spent studying as the Y-axis. If done this way, only one of the numbers needs to be quantitative.

 

[samoward]

Ok thanks alot, I had already converted the study time into numbers when creating tables, and the scatter graph has seemed to work when I do the same with internet speeds. Thanks!

New dilemma, I'm trying to create a bubble graph to show the most common answers (scatter graph doesn't show this, markers are just on top of each other) but for some reason the bubbles are all the same size. Any suggestions?

 

[xenou]

I've never used a bubble graph I'm afraid ... not sure