Problem: Calculating sums in Excel

Problem

Data: http://media.nek.lu.se/data/Sums.xlsx

Use Excel to solve this problem. Calculate

\(\sum_{i=1}^{n}{ {\left( x_i-\bar{x} \right)}^2 }\) as \((n-1)\) times the sample variance (use var.s function)

\(\sum_{i=1}^{n}{ {\left( x_i-\bar{x} \right)}^2 }\) as \(\sum_{i=1}^{n}{ x_i^2 }-n{\bar{x}}^2\) (use sumsq function)

\(\sum_{i=1}^{n}{ \left( x_i-\bar{x} \right)\left( y_i-\bar{y} \right) }\) as \((n-1)\) times the sample covariance (use covariance.s function)

\(\sum_{i=1}^{n}{ \left( x_i-\bar{x} \right)\left( y_i-\bar{y} \right) }\) as \(\sum_{i=1}^{n}{ x_iy_i }-n\bar{x}\bar{y}\) . You must first complete the C-column labeled “x*y”.

Check that you have the same result in a and b and in c and d