A linear regression analysis is employed to assess sales within the framework of modeling. The linear regression analysis supposes a linear relationship between the dependent variable, which is scaled metrically, and one or more independent variables.
The regression function proceeds as follows:
(1) y = b + ∑ b * x + e i 0 k∈K k k,i i
Whereby: yi:
Value of the i-th observation for the dependent variable, i.e. sales
x(k,i): Value of the i-th observation for the k-th independent variable, i.e. clicks on SEA Adwords or clicks on display banners b0:
Constant of the regression function, i.e. sales, without advertising services
bk:
Regression coefficient for the mapping of the k-th independent variable‘s influence, i.e. the degree of influence of SEA Adwords campaigns on total performance (sales)
ei:
Residuum of the i-th observation
I: K:
Index sets of the observations Index sets of the variables
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