In: Statistics and Probability
Wal-Mart is the second-largest retailer in the world. The data file (Wal-Mart Revenue 2004-2009 data.xlsx) is posted below the case study two file, and it holds monthly data on Wal-Mart’s revenue, along with several possibly related economic variables.
Identify and delete those five cases (rows) corresponding to December revenue. Then, use the new data set (without the December data) to complete the following problems.
R² | 0.716 | |||||
Adjusted R² | 0.703 | |||||
R | 0.846 | |||||
Std. Error | 2.406 | |||||
n | 68 | |||||
k | 3 | |||||
Dep. Var. | Revenue | |||||
ANOVA table | ||||||
Source | SS | df | MS | F | p-value | |
Regression | 935.1778 | 3 | 311.7259 | 53.85 | 1.72E-17 | |
Residual | 370.5055 | 64 | 5.7891 | |||
Total | 1,305.6833 | 67 | ||||
Regression output | confidence interval | |||||
variables | coefficients | std. error | t (df=64) | p-value | 95% lower | 95% upper |
Intercept | 58.6340 | |||||
CPI | -0.2915 | 0.0693 | -4.206 | .0001 | -0.4299 | -0.1531 |
Personal Consumption | 0.00001247 | 0.00000243 | 5.136 | 2.84E-06 | 0.00000762 | 0.00001732 |
Retail Sales Index | 0.00005849 | 0.00001080 | 5.415 | 9.83E-07 | 0.00003691 | 0.00008006 |
The multiple linear regression model to predict Wal-Mart's revenue, using CPI, Personal Consumption, and Retail Sales Index as the independent variables is:
Revenue = 58.6340 - 0.2915*CPI + 0.00001247*Personal Consumption + 0.00005849*Retail Sales Index
The residual plots are:
Wal-Mart’s revenue is closely related to the general state of the economy.