# Will anyone please calculate P-value for me! - or show me how to?

• Jan 10th 2013, 02:15 PM
TTrold
Will anyone please calculate P-value for me! - or show me how to?
Dear Friends.

I am currently doing my master thesis on GHGs from hydroelectric reservoirs. I have, however, run into a situation where I would very much like to find the p-value for one of the trendlines Excel have generated for me. (I know p will be far off, but still). I have tried to look through toturials at youtube and google, but I have not had the luck to find anything useful. Will anyone please help me calculate a p-value for me if I provide the data in .xlsx format?? (Worried)

The trendline (for tropical reservoirs only!) is based on a graph made from a number of samples in which y is the amount of GHG's over the reservoir (in mg/day) and x is the age of the reservoir (in days). The trendline equation for

CO2 is: 1173.3ln(x)-13117, and for;
CH4: 8.8779ln(x)-152.28

I have no idea how to find the p-values based on this information. The graphs are found on the tab named "overall". the data is found on the tab named "reservoir-list",, CO2 is column <I> and CH4 is column <J>, days are found in column <S>., again I am only interested in tropical reservoirs in this matter.. "biome" is found in column <K>.

I will even buy you a song or a cheap app on itunes if you help me
(Cool)
• Jan 10th 2013, 04:32 PM
chiro
Re: Will anyone please calculate P-value for me! - or show me how to?
Hey TTrold.

To find a p-value you need to have a distribution and some parameters. In this case it will be a t-distribution.

In Excel do you have a command to find the standard errors of the parameter estimates? This will give you answer you require.
• Jan 10th 2013, 11:32 PM
TTrold
Re: Will anyone please calculate P-value for me! - or show me how to?
Unfortunately data analysis tools are not included in Excel for Mac, which is partly the reason why I have given up on this :S I hoped it would be easy for someone just to plug the data in - damn! ;)
• Jan 10th 2013, 11:42 PM
chiro
Re: Will anyone please calculate P-value for me! - or show me how to?
You should be able to calculate the standard errors in Excel if you can get the parameter estimates for the regression (which you have got).