# Physics lab

Discussion in 'Community Discussion' started by jellz, Sep 15, 2007.

1. ### jellz macrumors regular

Joined:
May 5, 2007
#1
Alrighty, my lab asks me to find the slope and coefficient of regression for the best fit line on this graph. Can anyone tell me how I do this in excel? I tried google, and went to microsoft's, but didn't really understand it. thanks in advance! O it's excel 2007.

2. ### swiftaw macrumors 603

Joined:
Jan 31, 2005
Location:
Omaha, NE, USA
3. ### Abstract macrumors Penryn

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Dec 27, 2002
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#3
Did you try right-clicking on the graph and clicking on "Add Trendline"?

There should be an option that allows you to add the equation of that fitted line, along with the "R" value.

4. ### swiftaw macrumors 603

Joined:
Jan 31, 2005
Location:
Omaha, NE, USA
#4
On a side note, as a statistician, I go crazy every time anyone wants me to do statistical analysis in Excel.

5. ### jellz thread starter macrumors regular

Joined:
May 5, 2007
#5
hmm. I got two ways now and 2 different answers. First, I tried abstract's way and got a slope of 3.042 and a Rsquared value of .995. The second way was I entered the values on the spreadsheet and went to "more formulas" and had it calculate the slope and the Rsquared value with the data. With this method I got a slope of 3.098 and Rsquared value of .997

6. ### swiftaw macrumors 603

Joined:
Jan 31, 2005
Location:
Omaha, NE, USA
#6
Perhaps the second way fixes the intercept at 0?

7. ### jellz thread starter macrumors regular

Joined:
May 5, 2007
#7
Oh, I fixed the intercept at 0 with the first results. It's an area of a circle versus Radii squared graph. With the data I didn't bother entering 0,0 in. I guess I'll go with the first set of numbers.