Data prep for modeling

Data Summary: The variables: store, and holiday flag are continuous, but should be categorical
##      Store        Date            Weekly_Sales      Holiday_Flag    
##  Min.   : 1   Length:6435        Min.   : 209986   Min.   :0.00000  
##  1st Qu.:12   Class :character   1st Qu.: 553350   1st Qu.:0.00000  
##  Median :23   Mode  :character   Median : 960746   Median :0.00000  
##  Mean   :23                      Mean   :1046965   Mean   :0.06993  
##  3rd Qu.:34                      3rd Qu.:1420159   3rd Qu.:0.00000  
##  Max.   :45                      Max.   :3818686   Max.   :1.00000  
##   Temperature       Fuel_Price         CPI         Unemployment   
##  Min.   : -2.06   Min.   :2.472   Min.   :126.1   Min.   : 3.879  
##  1st Qu.: 47.46   1st Qu.:2.933   1st Qu.:131.7   1st Qu.: 6.891  
##  Median : 62.67   Median :3.445   Median :182.6   Median : 7.874  
##  Mean   : 60.66   Mean   :3.359   Mean   :171.6   Mean   : 7.999  
##  3rd Qu.: 74.94   3rd Qu.:3.735   3rd Qu.:212.7   3rd Qu.: 8.622  
##  Max.   :100.14   Max.   :4.468   Max.   :227.2   Max.   :14.313
Data Summary now with categorical variables as factors, and a random variable for splitting the data
##      Store          Date            Weekly_Sales     Holiday_Flag
##  1      : 143   Length:6435        Min.   : 209986   0:5985      
##  2      : 143   Class :character   1st Qu.: 553350   1: 450      
##  3      : 143   Mode  :character   Median : 960746               
##  4      : 143                      Mean   :1046965               
##  5      : 143                      3rd Qu.:1420159               
##  6      : 143                      Max.   :3818686               
##  (Other):5577                                                    
##   Temperature       Fuel_Price         CPI         Unemployment   
##  Min.   : -2.06   Min.   :2.472   Min.   :126.1   Min.   : 3.879  
##  1st Qu.: 47.46   1st Qu.:2.933   1st Qu.:131.7   1st Qu.: 6.891  
##  Median : 62.67   Median :3.445   Median :182.6   Median : 7.874  
##  Mean   : 60.66   Mean   :3.359   Mean   :171.6   Mean   : 7.999  
##  3rd Qu.: 74.94   3rd Qu.:3.735   3rd Qu.:212.7   3rd Qu.: 8.622  
##  Max.   :100.14   Max.   :4.468   Max.   :227.2   Max.   :14.313  
##                                                                   
##      random         
##  Min.   :0.0001067  
##  1st Qu.:0.2511800  
##  Median :0.5092787  
##  Mean   :0.5030516  
##  3rd Qu.:0.7480175  
##  Max.   :0.9994411  
## 
## tibble [6,435 × 9] (S3: tbl_df/tbl/data.frame)
##  $ Store       : Factor w/ 45 levels "1","2","3","4",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ Date        : chr [1:6435] "05-02-2010" "12-02-2010" "19-02-2010" "26-02-2010" ...
##  $ Weekly_Sales: num [1:6435] 1643691 1641957 1611968 1409728 1554807 ...
##  $ Holiday_Flag: Factor w/ 2 levels "0","1": 1 2 1 1 1 1 1 1 1 1 ...
##  $ Temperature : num [1:6435] 42.3 38.5 39.9 46.6 46.5 ...
##  $ Fuel_Price  : num [1:6435] 2.57 2.55 2.51 2.56 2.62 ...
##  $ CPI         : num [1:6435] 211 211 211 211 211 ...
##  $ Unemployment: num [1:6435] 8.11 8.11 8.11 8.11 8.11 ...
##  $ random      : num [1:6435] 0.8636 0.0275 0.8042 0.9408 0.9015 ...

Data split 70/30 into training and validation datasets.

Linear model to predict sales

  1. A linear model was created using all possible predictors, except for Date, predicting sales. This model allowed for the understanding of the individual effects of each predictor.
  2. Then a model with all possible interactions was created, again, excluding Date
  3. A backward selection was employed using alpha = 0.01 in order to obtain a more parsimonious model.
  4. The resulting model with interations, as well as the initial model without, can be found in the Appendix
## Backward Elimination Method 
## ---------------------------
## 
## Candidate Terms: 
## 
## 1. Store 
## 2. Holiday_Flag 
## 3. Temperature 
## 4. Fuel_Price 
## 5. CPI 
## 6. Unemployment 
## 7. Store:Holiday_Flag 
## 8. Store:Temperature 
## 9. Store:Fuel_Price 
## 10. Store:CPI 
## 11. Store:Unemployment 
## 12. Holiday_Flag:Temperature 
## 13. Holiday_Flag:Fuel_Price 
## 14. Holiday_Flag:CPI 
## 15. Holiday_Flag:Unemployment 
## 16. Temperature:Fuel_Price 
## 17. Temperature:CPI 
## 18. Temperature:Unemployment 
## 19. Fuel_Price:CPI 
## 20. Fuel_Price:Unemployment 
## 21. CPI:Unemployment 
## 
## 
## Step   => 0 
## Model  => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Unemployment + Store:Holiday_Flag + Store:Temperature + Store:Fuel_Price + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Holiday_Flag:Fuel_Price + Holiday_Flag:CPI + Holiday_Flag:Unemployment + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + Fuel_Price:Unemployment + CPI:Unemployment 
## R2     => 0.932 
## 
## Initiating stepwise selection... 
## 
## Step     => 1 
## Removed  => Holiday_Flag:CPI 
## Model    => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Unemployment + Store:Holiday_Flag + Store:Temperature + Store:Fuel_Price + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Holiday_Flag:Fuel_Price + Holiday_Flag:Unemployment + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + Fuel_Price:Unemployment + CPI:Unemployment 
## R2       => 0.9322 
## 
## Step     => 2 
## Removed  => Holiday_Flag:Unemployment 
## Model    => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Unemployment + Store:Holiday_Flag + Store:Temperature + Store:Fuel_Price + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Holiday_Flag:Fuel_Price + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + Fuel_Price:Unemployment + CPI:Unemployment 
## R2       => 0.9322 
## 
## Step     => 3 
## Removed  => Unemployment 
## Model    => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Store:Holiday_Flag + Store:Temperature + Store:Fuel_Price + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Holiday_Flag:Fuel_Price + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + Fuel_Price:Unemployment + CPI:Unemployment 
## R2       => 0.9322 
## 
## Step     => 4 
## Removed  => Fuel_Price:Unemployment 
## Model    => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Store:Holiday_Flag + Store:Temperature + Store:Fuel_Price + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Holiday_Flag:Fuel_Price + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + CPI:Unemployment 
## R2       => 0.9322 
## 
## Step     => 5 
## Removed  => Holiday_Flag:Fuel_Price 
## Model    => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Store:Holiday_Flag + Store:Temperature + Store:Fuel_Price + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + CPI:Unemployment 
## R2       => 0.93219 
## 
## Step     => 6 
## Removed  => CPI:Unemployment 
## Model    => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Store:Holiday_Flag + Store:Temperature + Store:Fuel_Price + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI 
## R2       => 0.93218 
## 
## 
## No more variables to be removed.
## 
## Variables Removed: 
## 
## => Holiday_Flag:CPI 
## => Holiday_Flag:Unemployment 
## => Unemployment 
## => Fuel_Price:Unemployment 
## => Holiday_Flag:Fuel_Price 
## => CPI:Unemployment

Interpretations of three predictors

The R^2 of the model (calculated on the validation data) is 0.9252588

Appendix

Model without interactions
## 
## Call:
## lm(formula = Weekly_Sales ~ . - Date, data = trainlm)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -521372  -69198  -10988   39000 1839948 
## 
## Coefficients:
##                 Estimate Std. Error t value Pr(>|t|)    
## (Intercept)    1476404.3   269418.4   5.480 4.49e-08 ***
## Store2          376211.4    22812.9  16.491  < 2e-16 ***
## Store3        -1161932.4    23308.5 -49.850  < 2e-16 ***
## Store4          682057.0   112906.2   6.041 1.66e-09 ***
## Store5        -1263279.0    23680.1 -53.348  < 2e-16 ***
## Store6           -2067.0    23055.8  -0.090 0.928569    
## Store7         -935684.8    34608.5 -27.036  < 2e-16 ***
## Store8         -681611.6    23464.4 -29.049  < 2e-16 ***
## Store9        -1046003.3    23673.2 -44.185  < 2e-16 ***
## Store10         570399.2   109778.8   5.196 2.13e-07 ***
## Store11        -210310.0    22875.7  -9.194  < 2e-16 ***
## Store12        -212997.5   103146.2  -2.065 0.038980 *  
## Store13         599878.7   110993.2   5.405 6.83e-08 ***
## Store14         556189.8    42007.9  13.240  < 2e-16 ***
## Store15        -744702.5   102513.7  -7.264 4.40e-13 ***
## Store16       -1022803.6    38358.8 -26.664  < 2e-16 ***
## Store17        -507761.3   112031.7  -4.532 5.99e-06 ***
## Store18        -282429.2   100314.1  -2.815 0.004892 ** 
## Store19          71247.2   102760.3   0.693 0.488136    
## Store20         546816.0    24883.9  21.975  < 2e-16 ***
## Store21        -795895.3    22590.4 -35.232  < 2e-16 ***
## Store22        -345210.7    97313.4  -3.547 0.000393 ***
## Store23         -88037.2   109424.0  -0.805 0.421122    
## Store24         -24488.0   101770.5  -0.241 0.809861    
## Store25        -835621.0    25087.8 -33.308  < 2e-16 ***
## Store26        -383034.7   102236.2  -3.747 0.000182 ***
## Store27         397733.3    98022.7   4.058 5.04e-05 ***
## Store28         104966.9   103355.7   1.016 0.309881    
## Store29        -797758.2    98667.1  -8.085 7.92e-16 ***
## Store30       -1106669.4    22699.1 -48.754  < 2e-16 ***
## Store31        -160010.4    23116.7  -6.922 5.09e-12 ***
## Store32        -318823.6    34478.4  -9.247  < 2e-16 ***
## Store33       -1070457.9   109189.3  -9.804  < 2e-16 ***
## Store34        -357805.9   104847.8  -3.413 0.000649 ***
## Store35        -452792.2    95562.3  -4.738 2.22e-06 ***
## Store36       -1164983.6    23039.9 -50.564  < 2e-16 ***
## Store37       -1014412.2    22705.9 -44.676  < 2e-16 ***
## Store38        -836107.5   103118.7  -8.108 6.58e-16 ***
## Store39         -63503.9    22659.7  -2.803 0.005093 ** 
## Store40        -489429.0   109486.2  -4.470 8.01e-06 ***
## Store41        -242951.4    36937.9  -6.577 5.34e-11 ***
## Store42        -780236.5   109692.0  -7.113 1.32e-12 ***
## Store43        -837938.2    25301.2 -33.119  < 2e-16 ***
## Store44       -1100178.0   111588.5  -9.859  < 2e-16 ***
## Store45        -673125.8    42171.2 -15.962  < 2e-16 ***
## Holiday_Flag1    68726.9     9493.6   7.239 5.29e-13 ***
## Temperature       -768.0      157.1  -4.889 1.05e-06 ***
## Fuel_Price      -37785.4     8544.5  -4.422 1.00e-05 ***
## CPI               1971.2     1224.8   1.609 0.107590    
## Unemployment    -24648.8     5093.7  -4.839 1.35e-06 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 159700 on 4456 degrees of freedom
## Multiple R-squared:  0.9213, Adjusted R-squared:  0.9204 
## F-statistic:  1064 on 49 and 4456 DF,  p-value: < 2.2e-16
Model with interactions
## 
## Call:
## lm(formula = paste(response, "~", paste(c(include, cterms), collapse = " + ")), 
##     data = l)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -615190  -55043   -9284   31776 1688212 
## 
## Coefficients:
##                             Estimate Std. Error t value Pr(>|t|)    
## (Intercept)               -7.784e+06  3.325e+06  -2.341 0.019278 *  
## Store2                    -1.448e+06  5.378e+06  -0.269 0.787736    
## Store3                    -2.558e+06  4.118e+06  -0.621 0.534464    
## Store4                     5.445e+06  5.715e+06   0.953 0.340845    
## Store5                    -3.285e+06  4.029e+06  -0.815 0.414934    
## Store6                    -1.191e+07  4.419e+06  -2.696 0.007041 ** 
## Store7                    -1.018e+07  4.602e+06  -2.212 0.027039 *  
## Store8                    -4.216e+06  3.574e+06  -1.180 0.238128    
## Store9                    -4.062e+06  4.254e+06  -0.955 0.339616    
## Store10                    7.908e+06  6.312e+06   1.253 0.210291    
## Store11                   -6.479e+06  3.842e+06  -1.686 0.091815 .  
## Store12                   -3.929e+06  5.591e+06  -0.703 0.482328    
## Store13                    1.581e+07  8.209e+06   1.926 0.054197 .  
## Store14                    6.594e+06  3.100e+06   2.127 0.033444 *  
## Store15                    1.590e+06  2.858e+06   0.556 0.577946    
## Store16                   -4.478e+06  4.489e+06  -0.998 0.318554    
## Store17                    6.649e+05  4.023e+06   0.165 0.868715    
## Store18                    2.648e+06  5.014e+06   0.528 0.597474    
## Store19                    1.599e+06  2.871e+06   0.557 0.577529    
## Store20                   -3.126e+06  2.893e+06  -1.080 0.280051    
## Store21                   -1.191e+07  5.327e+06  -2.236 0.025392 *  
## Store22                   -4.229e+06  4.685e+06  -0.903 0.366687    
## Store23                    2.675e+06  5.396e+06   0.496 0.620152    
## Store24                    2.231e+04  3.299e+06   0.007 0.994604    
## Store25                   -2.839e+06  2.964e+06  -0.958 0.338123    
## Store26                   -1.271e+06  5.727e+06  -0.222 0.824333    
## Store27                    5.106e+06  2.844e+06   1.795 0.072655 .  
## Store28                    7.170e+06  5.866e+06   1.222 0.221683    
## Store29                   -8.769e+05  4.399e+06  -0.199 0.842025    
## Store30                    1.348e+06  5.292e+06   0.255 0.798894    
## Store31                   -8.720e+06  5.212e+06  -1.673 0.094389 .  
## Store32                   -1.068e+07  4.663e+06  -2.291 0.022005 *  
## Store33                    1.244e+06  5.955e+06   0.209 0.834499    
## Store34                    4.783e+05  3.656e+06   0.131 0.895910    
## Store35                    3.396e+05  2.852e+06   0.119 0.905201    
## Store36                    3.393e+06  5.037e+06   0.674 0.500571    
## Store37                   -2.470e+05  5.027e+06  -0.049 0.960818    
## Store38                   -1.812e+05  4.992e+06  -0.036 0.971051    
## Store39                   -1.630e+07  4.821e+06  -3.380 0.000731 ***
## Store40                    3.833e+06  5.619e+06   0.682 0.495170    
## Store41                   -1.991e+07  5.883e+06  -3.384 0.000721 ***
## Store42                    5.233e+06  6.710e+06   0.780 0.435561    
## Store43                   -4.982e+05  3.074e+06  -0.162 0.871254    
## Store44                    4.248e+06  8.083e+06   0.526 0.599204    
## Store45                   -2.910e+06  3.130e+06  -0.930 0.352492    
## Holiday_Flag1             -4.523e+04  7.370e+04  -0.614 0.539444    
## Temperature                6.303e+04  1.915e+04   3.291 0.001006 ** 
## Fuel_Price                 2.010e+06  6.676e+05   3.010 0.002626 ** 
## CPI                        4.651e+04  1.445e+04   3.218 0.001301 ** 
## Store2:Holiday_Flag1       6.671e+04  8.679e+04   0.769 0.442150    
## Store3:Holiday_Flag1      -5.017e+04  9.179e+04  -0.547 0.584692    
## Store4:Holiday_Flag1       8.443e+04  8.676e+04   0.973 0.330538    
## Store5:Holiday_Flag1      -5.642e+04  9.142e+04  -0.617 0.537183    
## Store6:Holiday_Flag1       7.768e+04  8.856e+04   0.877 0.380469    
## Store7:Holiday_Flag1       1.084e+05  8.905e+04   1.217 0.223696    
## Store8:Holiday_Flag1      -1.925e+04  8.862e+04  -0.217 0.828021    
## Store9:Holiday_Flag1      -2.665e+04  9.494e+04  -0.281 0.778981    
## Store10:Holiday_Flag1      1.501e+05  9.504e+04   1.580 0.114208    
## Store11:Holiday_Flag1     -6.607e+04  8.845e+04  -0.747 0.455083    
## Store12:Holiday_Flag1     -9.407e+04  9.757e+04  -0.964 0.335076    
## Store13:Holiday_Flag1      1.202e+05  8.792e+04   1.367 0.171568    
## Store14:Holiday_Flag1     -1.038e+05  8.906e+04  -1.165 0.243898    
## Store15:Holiday_Flag1      6.733e+04  8.893e+04   0.757 0.449047    
## Store16:Holiday_Flag1      9.098e+04  9.987e+04   0.911 0.362383    
## Store17:Holiday_Flag1      9.902e+04  8.871e+04   1.116 0.264379    
## Store18:Holiday_Flag1      3.855e+04  9.961e+04   0.387 0.698778    
## Store19:Holiday_Flag1      9.483e+04  8.545e+04   1.110 0.267120    
## Store20:Holiday_Flag1     -2.877e+03  9.331e+04  -0.031 0.975403    
## Store21:Holiday_Flag1      1.694e+04  9.999e+04   0.169 0.865481    
## Store22:Holiday_Flag1     -1.014e+05  1.131e+05  -0.897 0.369948    
## Store23:Holiday_Flag1      1.925e+04  9.098e+04   0.212 0.832416    
## Store24:Holiday_Flag1      1.175e+05  9.481e+04   1.239 0.215456    
## Store25:Holiday_Flag1     -5.491e+04  8.977e+04  -0.612 0.540820    
## Store26:Holiday_Flag1      8.527e+04  9.146e+04   0.932 0.351209    
## Store27:Holiday_Flag1      1.122e+05  8.535e+04   1.314 0.188839    
## Store28:Holiday_Flag1      8.557e+04  9.425e+04   0.908 0.363977    
## Store29:Holiday_Flag1      4.579e+04  8.972e+04   0.510 0.609822    
## Store30:Holiday_Flag1     -8.289e+04  9.419e+04  -0.880 0.378889    
## Store31:Holiday_Flag1     -2.912e+04  1.046e+05  -0.278 0.780744    
## Store32:Holiday_Flag1     -5.947e+04  9.111e+04  -0.653 0.513958    
## Store33:Holiday_Flag1     -8.181e+04  8.706e+04  -0.940 0.347409    
## Store34:Holiday_Flag1     -1.098e+04  8.848e+04  -0.124 0.901240    
## Store35:Holiday_Flag1      1.012e+05  9.823e+04   1.030 0.302997    
## Store36:Holiday_Flag1     -7.624e+04  9.741e+04  -0.783 0.433862    
## Store37:Holiday_Flag1     -8.889e+04  9.135e+04  -0.973 0.330569    
## Store38:Holiday_Flag1     -7.505e+04  8.697e+04  -0.863 0.388242    
## Store39:Holiday_Flag1      9.906e+04  9.562e+04   1.036 0.300245    
## Store40:Holiday_Flag1      2.409e+04  8.887e+04   0.271 0.786334    
## Store41:Holiday_Flag1      7.114e+04  8.896e+04   0.800 0.423956    
## Store42:Holiday_Flag1     -8.792e+04  9.093e+04  -0.967 0.333651    
## Store43:Holiday_Flag1     -5.904e+04  8.690e+04  -0.679 0.496926    
## Store44:Holiday_Flag1     -5.263e+04  9.130e+04  -0.577 0.564304    
## Store45:Holiday_Flag1     -4.118e+04  9.853e+04  -0.418 0.675972    
## Store2:Temperature         6.091e+02  1.650e+03   0.369 0.712000    
## Store3:Temperature         2.536e+03  1.851e+03   1.370 0.170728    
## Store4:Temperature        -3.074e+04  8.124e+03  -3.783 0.000157 ***
## Store5:Temperature         1.515e+03  1.812e+03   0.836 0.403104    
## Store6:Temperature         2.950e+03  1.702e+03   1.733 0.083095 .  
## Store7:Temperature        -1.392e+03  2.489e+03  -0.559 0.575882    
## Store8:Temperature         6.539e+02  1.698e+03   0.385 0.700184    
## Store9:Temperature         1.905e+03  1.717e+03   1.109 0.267343    
## Store10:Temperature       -3.185e+04  7.957e+03  -4.002 6.38e-05 ***
## Store11:Temperature        1.665e+03  1.824e+03   0.913 0.361224    
## Store12:Temperature       -2.212e+04  7.578e+03  -2.919 0.003532 ** 
## Store13:Temperature       -2.674e+04  8.020e+03  -3.334 0.000862 ***
## Store14:Temperature       -9.149e+03  3.065e+03  -2.985 0.002851 ** 
## Store15:Temperature       -2.268e+04  7.413e+03  -3.060 0.002228 ** 
## Store16:Temperature       -2.687e+03  2.670e+03  -1.006 0.314285    
## Store17:Temperature       -2.467e+04  8.051e+03  -3.064 0.002197 ** 
## Store18:Temperature       -2.132e+04  7.308e+03  -2.917 0.003547 ** 
## Store19:Temperature       -2.246e+04  7.418e+03  -3.027 0.002484 ** 
## Store20:Temperature       -3.053e+03  1.756e+03  -1.739 0.082125 .  
## Store21:Temperature        2.839e+03  1.669e+03   1.701 0.089016 .  
## Store22:Temperature       -2.234e+04  7.042e+03  -3.172 0.001523 ** 
## Store23:Temperature       -2.343e+04  7.807e+03  -3.001 0.002703 ** 
## Store24:Temperature       -1.833e+04  7.379e+03  -2.483 0.013054 *  
## Store25:Temperature       -4.966e+02  1.799e+03  -0.276 0.782556    
## Store26:Temperature       -2.100e+04  7.396e+03  -2.840 0.004539 ** 
## Store27:Temperature       -1.764e+04  7.083e+03  -2.490 0.012814 *  
## Store28:Temperature       -2.338e+04  7.594e+03  -3.078 0.002094 ** 
## Store29:Temperature       -2.113e+04  7.199e+03  -2.935 0.003355 ** 
## Store30:Temperature        2.588e+03  1.632e+03   1.586 0.112702    
## Store31:Temperature        1.633e+03  1.686e+03   0.969 0.332757    
## Store32:Temperature       -4.166e+03  2.452e+03  -1.699 0.089428 .  
## Store33:Temperature       -2.374e+04  7.913e+03  -3.000 0.002711 ** 
## Store34:Temperature       -2.333e+04  7.577e+03  -3.079 0.002087 ** 
## Store35:Temperature       -1.901e+04  6.932e+03  -2.743 0.006123 ** 
## Store36:Temperature        2.942e+03  1.903e+03   1.546 0.122134    
## Store37:Temperature        2.013e+03  1.932e+03   1.042 0.297415    
## Store38:Temperature       -2.002e+04  7.568e+03  -2.646 0.008186 ** 
## Store39:Temperature        3.181e+03  1.861e+03   1.709 0.087498 .  
## Store40:Temperature       -2.461e+04  7.799e+03  -3.156 0.001612 ** 
## Store41:Temperature       -3.147e+03  2.590e+03  -1.215 0.224490    
## Store42:Temperature       -2.498e+04  7.988e+03  -3.128 0.001773 ** 
## Store43:Temperature        2.965e+03  1.880e+03   1.577 0.114839    
## Store44:Temperature       -2.436e+04  8.029e+03  -3.034 0.002430 ** 
## Store45:Temperature       -8.392e+03  3.108e+03  -2.700 0.006953 ** 
## Store2:Fuel_Price         -2.071e+05  9.328e+04  -2.221 0.026422 *  
## Store3:Fuel_Price         -3.785e+04  1.054e+05  -0.359 0.719462    
## Store4:Fuel_Price         -9.605e+05  2.840e+05  -3.382 0.000727 ***
## Store5:Fuel_Price         -9.066e+04  9.423e+04  -0.962 0.336033    
## Store6:Fuel_Price         -2.230e+05  8.963e+04  -2.488 0.012871 *  
## Store7:Fuel_Price         -2.603e+05  1.129e+05  -2.305 0.021217 *  
## Store8:Fuel_Price         -8.254e+04  9.043e+04  -0.913 0.361417    
## Store9:Fuel_Price         -4.605e+04  9.451e+04  -0.487 0.626064    
## Store10:Fuel_Price        -9.600e+05  2.873e+05  -3.342 0.000840 ***
## Store11:Fuel_Price        -1.420e+05  1.040e+05  -1.365 0.172197    
## Store12:Fuel_Price        -1.000e+06  2.873e+05  -3.482 0.000503 ***
## Store13:Fuel_Price        -7.374e+05  2.950e+05  -2.500 0.012466 *  
## Store14:Fuel_Price        -3.924e+05  1.290e+05  -3.042 0.002364 ** 
## Store15:Fuel_Price        -8.661e+05  2.661e+05  -3.255 0.001142 ** 
## Store16:Fuel_Price        -2.604e+05  1.226e+05  -2.125 0.033682 *  
## Store17:Fuel_Price        -8.718e+05  2.886e+05  -3.020 0.002540 ** 
## Store18:Fuel_Price        -1.011e+06  2.663e+05  -3.795 0.000150 ***
## Store19:Fuel_Price        -9.662e+05  2.668e+05  -3.621 0.000296 ***
## Store20:Fuel_Price        -2.508e+05  8.957e+04  -2.800 0.005131 ** 
## Store21:Fuel_Price        -1.804e+05  9.327e+04  -1.935 0.053096 .  
## Store22:Fuel_Price        -9.301e+05  2.561e+05  -3.632 0.000284 ***
## Store23:Fuel_Price        -8.518e+05  2.660e+05  -3.202 0.001373 ** 
## Store24:Fuel_Price        -9.360e+05  2.670e+05  -3.505 0.000461 ***
## Store25:Fuel_Price        -1.827e+05  9.094e+04  -2.009 0.044625 *  
## Store26:Fuel_Price        -8.890e+05  2.669e+05  -3.331 0.000873 ***
## Store27:Fuel_Price        -8.268e+05  2.536e+05  -3.260 0.001121 ** 
## Store28:Fuel_Price        -8.502e+05  2.949e+05  -2.883 0.003956 ** 
## Store29:Fuel_Price        -8.727e+05  2.658e+05  -3.283 0.001037 ** 
## Store30:Fuel_Price        -8.087e+04  9.322e+04  -0.868 0.385694    
## Store31:Fuel_Price        -1.175e+05  9.256e+04  -1.269 0.204449    
## Store32:Fuel_Price        -2.521e+05  1.136e+05  -2.219 0.026509 *  
## Store33:Fuel_Price        -9.182e+05  2.826e+05  -3.250 0.001165 ** 
## Store34:Fuel_Price        -9.563e+05  2.841e+05  -3.366 0.000769 ***
## Store35:Fuel_Price        -8.924e+05  2.541e+05  -3.512 0.000450 ***
## Store36:Fuel_Price        -7.547e+04  9.626e+04  -0.784 0.433080    
## Store37:Fuel_Price        -6.470e+04  9.692e+04  -0.668 0.504409    
## Store38:Fuel_Price        -9.114e+05  2.842e+05  -3.207 0.001352 ** 
## Store39:Fuel_Price        -3.272e+05  9.745e+04  -3.358 0.000792 ***
## Store40:Fuel_Price        -9.443e+05  2.644e+05  -3.572 0.000359 ***
## Store41:Fuel_Price        -2.231e+05  1.141e+05  -1.956 0.050515 .  
## Store42:Fuel_Price        -8.749e+05  2.866e+05  -3.053 0.002283 ** 
## Store43:Fuel_Price        -1.342e+05  1.018e+05  -1.319 0.187136    
## Store44:Fuel_Price        -8.809e+05  2.894e+05  -3.044 0.002352 ** 
## Store45:Fuel_Price        -3.530e+05  1.281e+05  -2.755 0.005888 ** 
## Store2:CPI                 8.877e+03  2.127e+04   0.417 0.676491    
## Store3:CPI                 4.932e+03  1.633e+04   0.302 0.762701    
## Store4:CPI                -2.426e+03  3.966e+04  -0.061 0.951230    
## Store5:CPI                 8.168e+03  1.569e+04   0.521 0.602692    
## Store6:CPI                 4.634e+04  1.744e+04   2.658 0.007900 ** 
## Store7:CPI                 3.906e+04  1.829e+04   2.135 0.032796 *  
## Store8:CPI                 1.374e+04  1.397e+04   0.983 0.325546    
## Store9:CPI                 1.104e+04  1.686e+04   0.655 0.512471    
## Store10:CPI               -2.362e+04  4.331e+04  -0.545 0.585527    
## Store11:CPI                2.474e+04  1.525e+04   1.622 0.104848    
## Store12:CPI                5.125e+04  3.876e+04   1.322 0.186223    
## Store13:CPI               -8.550e+04  5.820e+04  -1.469 0.141863    
## Store14:CPI               -2.760e+04  1.193e+04  -2.313 0.020775 *  
## Store15:CPI                3.607e+03  1.719e+04   0.210 0.833793    
## Store16:CPI                1.565e+04  1.714e+04   0.913 0.361512    
## Store17:CPI                1.775e+04  2.506e+04   0.709 0.478673    
## Store18:CPI                1.061e+04  2.825e+04   0.376 0.707179    
## Store19:CPI                1.686e+04  1.737e+04   0.971 0.331540    
## Store20:CPI                1.940e+04  1.127e+04   1.720 0.085431 .  
## Store21:CPI                4.210e+04  2.109e+04   1.996 0.046010 *  
## Store22:CPI                4.437e+04  2.585e+04   1.716 0.086171 .  
## Store23:CPI                4.115e+03  3.262e+04   0.126 0.899627    
## Store24:CPI                2.231e+04  2.594e+04   0.860 0.389811    
## Store25:CPI                8.676e+03  1.161e+04   0.747 0.454814    
## Store26:CPI                2.600e+04  3.000e+04   0.867 0.386252    
## Store27:CPI               -1.371e+04  1.814e+04  -0.756 0.449854    
## Store28:CPI               -2.996e+04  4.186e+04  -0.716 0.474166    
## Store29:CPI                1.914e+04  2.504e+04   0.764 0.444716    
## Store30:CPI               -1.030e+04  2.091e+04  -0.493 0.622225    
## Store31:CPI                3.304e+04  2.068e+04   1.598 0.110200    
## Store32:CPI                4.374e+04  1.846e+04   2.370 0.017844 *  
## Store33:CPI                6.294e+03  4.053e+04   0.155 0.876607    
## Store34:CPI                1.852e+04  2.205e+04   0.840 0.400908    
## Store35:CPI               -8.191e+03  1.569e+04  -0.522 0.601735    
## Store36:CPI               -2.109e+04  2.039e+04  -1.034 0.301105    
## Store37:CPI               -4.073e+03  2.026e+04  -0.201 0.840704    
## Store38:CPI                1.750e+04  3.394e+04   0.516 0.606200    
## Store39:CPI                6.986e+04  1.958e+04   3.568 0.000363 ***
## Store40:CPI               -1.074e+03  3.384e+04  -0.032 0.974676    
## Store41:CPI                8.242e+04  2.343e+04   3.518 0.000439 ***
## Store42:CPI               -1.838e+04  4.611e+04  -0.399 0.690195    
## Store43:CPI               -1.541e+03  1.254e+04  -0.123 0.902229    
## Store44:CPI               -1.392e+04  5.724e+04  -0.243 0.807923    
## Store45:CPI                8.262e+03  1.180e+04   0.700 0.483908    
## Store1:Unemployment       -3.149e+04  8.247e+04  -0.382 0.702636    
## Store2:Unemployment        3.734e+04  1.167e+05   0.320 0.749022    
## Store3:Unemployment        5.481e+03  9.687e+04   0.057 0.954877    
## Store4:Unemployment       -4.543e+04  4.324e+04  -1.051 0.293526    
## Store5:Unemployment        2.637e+04  1.141e+05   0.231 0.817292    
## Store6:Unemployment        3.138e+05  1.058e+05   2.967 0.003025 ** 
## Store7:Unemployment        2.668e+05  1.150e+05   2.321 0.020346 *  
## Store8:Unemployment        7.698e+04  9.761e+04   0.789 0.430370    
## Store9:Unemployment        5.699e+04  1.074e+05   0.531 0.595712    
## Store10:Unemployment       1.114e+04  7.527e+04   0.148 0.882346    
## Store11:Unemployment       1.346e+05  8.920e+04   1.509 0.131273    
## Store12:Unemployment       8.689e+04  4.672e+04   1.860 0.063007 .  
## Store13:Unemployment      -1.418e+05  9.384e+04  -1.511 0.130808    
## Store14:Unemployment       6.247e+04  1.541e+05   0.405 0.685295    
## Store15:Unemployment       8.233e+04  1.121e+05   0.735 0.462546    
## Store16:Unemployment       1.623e+05  1.660e+05   0.978 0.328348    
## Store17:Unemployment       1.327e+04  6.899e+04   0.192 0.847442    
## Store18:Unemployment      -4.998e+04  1.178e+05  -0.424 0.671315    
## Store19:Unemployment       2.206e+03  1.141e+05   0.019 0.984582    
## Store20:Unemployment       4.267e+04  8.561e+04   0.498 0.618171    
## Store21:Unemployment       2.861e+05  1.159e+05   2.469 0.013572 *  
## Store22:Unemployment       1.768e+05  1.152e+05   1.534 0.125036    
## Store23:Unemployment       2.048e+04  1.383e+05   0.148 0.882292    
## Store24:Unemployment       5.111e+04  1.332e+05   0.384 0.701160    
## Store25:Unemployment       7.060e+04  8.932e+04   0.791 0.429275    
## Store26:Unemployment       1.089e+05  1.805e+05   0.603 0.546356    
## Store27:Unemployment       3.373e+04  1.227e+05   0.275 0.783431    
## Store28:Unemployment       2.664e+04  4.565e+04   0.584 0.559499    
## Store29:Unemployment       9.706e+04  8.004e+04   1.213 0.225322    
## Store30:Unemployment      -5.095e+04  1.156e+05  -0.441 0.659316    
## Store31:Unemployment       1.921e+05  1.109e+05   1.732 0.083310 .  
## Store32:Unemployment       3.027e+05  1.203e+05   2.517 0.011882 *  
## Store33:Unemployment       6.491e+04  6.532e+04   0.994 0.320391    
## Store34:Unemployment       6.117e+04  4.620e+04   1.324 0.185566    
## Store35:Unemployment       4.276e+05  1.112e+05   3.846 0.000122 ***
## Store36:Unemployment      -2.844e+04  9.612e+04  -0.296 0.767310    
## Store37:Unemployment      -7.433e+03  9.779e+04  -0.076 0.939415    
## Store38:Unemployment       4.916e+04  4.306e+04   1.142 0.253602    
## Store39:Unemployment       2.312e+05  9.064e+04   2.551 0.010789 *  
## Store40:Unemployment      -8.040e+04  1.497e+05  -0.537 0.591229    
## Store41:Unemployment       6.053e+05  1.817e+05   3.330 0.000875 ***
## Store42:Unemployment      -4.567e+03  7.737e+04  -0.059 0.952936    
## Store43:Unemployment      -1.297e+03  5.405e+04  -0.024 0.980858    
## Store44:Unemployment       1.381e+03  9.126e+04   0.015 0.987925    
## Store45:Unemployment       2.254e+05  1.653e+05   1.363 0.172843    
## Holiday_Flag1:Temperature  1.785e+03  5.201e+02   3.432 0.000605 ***
## Temperature:Fuel_Price     2.149e+03  6.852e+02   3.136 0.001724 ** 
## Temperature:CPI           -3.087e+02  8.862e+01  -3.484 0.000499 ***
## Temperature:Unemployment  -8.473e+02  3.676e+02  -2.305 0.021232 *  
## Fuel_Price:CPI            -9.662e+03  3.075e+03  -3.142 0.001692 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 152100 on 4231 degrees of freedom
## Multiple R-squared:  0.9322, Adjusted R-squared:  0.9278 
## F-statistic: 212.2 on 274 and 4231 DF,  p-value: < 2.2e-16