The Student Room Group
Uni students - Complete our survey >>
Uni students - Complete our survey >>
Uni students - Complete our survey >>

Maths CW - correlating data?

Hi, for my maths CW i have to check if the data i've collected correlates, and this sounds stupid but I just cannot figure out how.

I'm using excel and just have 2 lists of numbers, I've been trying to check for a correlation by going Insert > Scatter and choosing a graph but all I get is a line.

Also, my maths teacher said i should get a number like 0.7 to show me how strong the correlation is and i am just getting nothing!!
I think you need to find the coefficient of the least squares regression line.
I do at some point for the CW - but the fgirst thing we're meant to do before wee do anything else, is use excel to check if our data correlates
Original post by deadsmurfette
I do at some point for the CW - but the fgirst thing we're meant to do before wee do anything else, is use excel to check if our data correlates


Oh soz can't help you then. We don't have any coursework for Maths.
Have you tried looking at the tutorials on Excel or just type your problem on google.
I am trying! Hopefully I'll find something soon - might just do the graph by hand to show the correlation.
Reply 5
Avatar for Ben121
Ben121
4
You have to add a trendline to your data, right click on a point and click add trend line, then when that dialog pops up there are a few options you can select to show certain parts of information.
Reply 6
Avatar for Pandora.
Pandora.
15
Maths coursework? Which exam board is this?
IB Maths Studies, not sure if IB have boards.
Reply 8
Avatar for Ayakashi
Ayakashi
Pearson Product Moment Correlation Coefficient AKA
PMCC or 'r' value shows how strong weak a correlation is, giving values between +1 and -1, that could be what your teacher was talking about 0.7 would be a mid-strong correlation.

I think you need to compare two values on one side to the other; forgot how to do on spreadsheet =x
Reply 9
Avatar for Pandora.
Pandora.
15
Original post by Ayakashi
Pearson Product Moment Correlation Coefficient AKA
PMCC or 'r' value shows how strong weak a correlation is, giving values between +1 and -1, that could be what your teacher was talking about 0.7 would be a mid-strong correlation.

I think you need to compare two values on one side to the other; forgot how to do on spreadsheet =x

Isn't this practically the same as Spearman's Rank?
Reply 10
Avatar for Ayakashi
Ayakashi
Original post by Pandora.
Isn't this practically the same as Spearman's Rank?



Sorry for late reply but yea they are the pretty much the same except Pearson uses the measures of all the data in a list, on the other hand Spearmans rank only uses their position in the list, therefore PMCC Is more accurate.

Spearmans rank can also be used where the data is non-numeric like People expressing things an order in which things they like, Spearmans 'rank' you can tell by rank that differing things will be ranked differently and so has a formula for the 'rank' of the object of whatever.

Spearmans rank and PMCC will come out with very similar values like 0.35 for Pmcc and 0.37 for spearmans rank.
I managed to do it in the end :smile:
Was actually pretty simple - my Dad helped me and for a while he couldn't do it either, but then he tried what I'd been trying and it worked for him :smile:
And yeah it was pearsons product thing but I was just having trouble doing the graph :tongue:

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you