Linear regression in matlab

Hi,

I have two variables as text files loaded in Matlab.

They are vegeation cover (dependent variable ) and temperature (independent variable)

I want to use linear regression analysis to estimate the proportion (as a percentage) of variance in vegetation cover controlled by variance in air temperature.

I do not understand the 'variance' part?

Code so far...

S = load('../vegetation.txt')
% Load air temperature
T = load('../airtemp.txt')
% calculate linear regression
mdl = fitlm(S, T, 'linear', 'RobustOpts','on');

Thank you.

[Image Analyst]

I don't either. But you're the one who said it, not me. Didn't you?

Are you trying to use Principal Components Analysis to try to find the variation in vegetation cover that is explained by variation in the first or second Principal Component?

Or are you merely trying to fit a line through the data and compute the residuals?