Which variable is most strongly associated with the number of pizzas sold? Please provide explanations regarding choice.
As shown in Table 1, the dependent variable (Y) which is the quantity sold each month for each outlet is found in column 2. The explanatory variables are found in columns 3, 4 and 5, namely: average price of deep-dish pizza in dollars (X1), monthly advertising expenditures in dollars (X2), and disposable income per household in dollars (X3).
To assist in the computations the software SPSS for Windows (2001) Version 11.0.0 was used. Figure 1 presents the mean and standard deviation as two of the three descriptive measures used in the first part of the statistical analysis.
As reflected in Figure 1, the average quantity of deep-dish pizza sold in all 15 outlets of the Original Italian Pizza restaurant chain is 63,740. The computed standard deviation in the quantity sold among the 15 outlets is 13,168.404. Meanwhile, the average price of pizza for the month is $11.46 and with a standard deviation of $0.978 among the 15 outlets. The average advertising expense for the month considering all 15 outlets is $54,933.33 and the standard deviation of the advertising costs is $7,009.042. The average disposable income per household in the areas surrounding the outlets is $41,540.00, and these values registered a standard deviation of $2,165.575.
The coefficient of variation for the dependent and explanatory variables were also computed manually, to allow for comparisons across the variables. The coefficient of variation (vc) expresses the standard deviation as a proportion of the mean, or the quotient between the standard deviation (s) and the mean (), multiplied by 100% (Portney and Watkins, 2009).
The dependent variable, quantity sold has a coefficient of variation, vc = 20.66. The explanatory variables have the ...