In: Math
Create an excel worksheet and populate it, in columns, with values of X that are -2, -1, 0, 1, 2 and values of Y that are -1, 1,1,1,3. As an aside, note that the sample mean of X is 0. Create the columns shown below, and enter the proper formulas into excel.
| 
 (X minus  | 
 (X minus mean)  | 
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| 
 Mean)  | 
 times (Y  | 
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| 
 Y  | 
 Y-mean  | 
 X  | 
 X-mean  | 
 squared  | 
 minus mean)  | 
 Y-hat  | 
 u-hat  | 
|
| 
 -1  | 
 -2  | 
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| 
 1  | 
 -1  | 
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| 
 1  | 
 0  | 
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| 
 1  | 
 1  | 
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| 
 3  | 
 2  | 
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| 
 sum  | 
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| 
 sum*1/n  | 
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| 
 B1-hat =  | 
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| 
 B0-hat =  | 
| (X minus | (X minus mean) | |||||||||
| Mean) | times (Y | |||||||||
| Y | Y-mean | X | X-mean | squared | minus mean) | Y-hat | u-hat | (x-mean)(y-mean) | ||
| -1 | -2 | -2 | -2 | 4 | 4 | 4 | ||||
| 1 | 0 | -1 | -1 | 1 | 0 | 0 | ||||
| 1 | 0 | 0 | 0 | 0 | 0 | 0 | ||||
| 1 | 0 | 1 | 1 | 1 | 0 | 0 | ||||
| 3 | 2 | 2 | 2 | 4 | 4 | 4 | ||||
| sum | 5 | 0 | 0 | 0 | 10 | 8 | 1 | 0 | 8 | |
| sum*1/n | 1 | 0 | 0 | 0 | 2 | 1.6 | ||||
| B1-hat = | 0.8 | |||||||||
| B0-hat = | 1 | 

Formulas used are:
