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   Min.   :0.00000  
##  2      : 143   Class :character   1st Qu.: 553350   1st Qu.:0.00000  
##  3      : 143   Mode  :character   Median : 960746   Median :0.00000  
##  4      : 143                      Mean   :1046965   Mean   :0.06993  
##  5      : 143                      3rd Qu.:1420159   3rd Qu.:0.00000  
##  6      : 143                      Max.   :3818686   Max.   :1.00000  
##  (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.   :0.0000653  
##  1st Qu.:0.2527042  
##  Median :0.4945870  
##  Mean   :0.4980825  
##  3rd Qu.:0.7453083  
##  Max.   :0.9999414  
## 
## 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: num [1:6435] 0 1 0 0 0 0 0 0 0 0 ...
##  $ 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] 0.288 0.788 0.409 0.883 0.94 ...

Data split 70/30 into training and validation datasets.

The training data has 4533 observations

The validation data has 1902 observations

  1. Linear model to predict sales
  2. 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.
  3. Then a model with all possible interactions was created, again, excluding Date
  4. A backward selection was employed using alpha = 0.01 in order to obtain a more parsimonious model.
  5. 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     => 0.93 
## 
## Initiating stepwise selection... 
## 
## Step     => 1 
## 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 + Holiday_Flag:CPI + Holiday_Flag:Unemployment + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + Fuel_Price:Unemployment + CPI:Unemployment 
## R2       => 0.93027 
## 
## Step     => 2 
## Removed  => Holiday_Flag:CPI 
## 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 + Holiday_Flag:Unemployment + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + Fuel_Price:Unemployment + CPI:Unemployment 
## R2       => 0.93027 
## 
## Step     => 3 
## 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 + Holiday_Flag:Unemployment + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI + CPI:Unemployment 
## R2       => 0.93027 
## 
## Step     => 4 
## 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 + Holiday_Flag:Fuel_Price + Holiday_Flag:Unemployment + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI 
## R2       => 0.93026 
## 
## Step     => 5 
## Removed  => Store:Fuel_Price 
## Model    => Weekly_Sales ~ Store + Holiday_Flag + Temperature + Fuel_Price + CPI + Store:Holiday_Flag + Store:Temperature + Store:CPI + Store:Unemployment + Holiday_Flag:Temperature + Holiday_Flag:Fuel_Price + Holiday_Flag:Unemployment + Temperature:Fuel_Price + Temperature:CPI + Temperature:Unemployment + Fuel_Price:CPI 
## R2       => 0.92952 
## 
## 
## No more variables to be removed.
## 
## Variables Removed: 
## 
## => Unemployment 
## => Holiday_Flag:CPI 
## => Fuel_Price:Unemployment 
## => CPI:Unemployment 
## => Store:Fuel_Price

Interpretations of three predictors

The R^2 of the model (calculated on the validation data) is 0.9203449

Appendix

Model without interactions

## 
## Call:
## lm(formula = Weekly_Sales ~ . - Date, data = trainlm)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -513804  -69546  -11882   39468 1823766 
## 
## Coefficients:
##                Estimate Std. Error t value Pr(>|t|)    
## (Intercept)   1357543.2   278781.6   4.870 1.16e-06 ***
## Store2         351630.2    22573.7  15.577  < 2e-16 ***
## Store3       -1180716.9    23170.7 -50.957  < 2e-16 ***
## Store4         716535.6   116599.9   6.145 8.68e-10 ***
## Store5       -1282576.3    24140.1 -53.131  < 2e-16 ***
## Store6         -42348.2    23255.9  -1.821 0.068679 .  
## Store7        -946003.2    35215.5 -26.863  < 2e-16 ***
## Store8        -699172.6    23983.0 -29.153  < 2e-16 ***
## Store9       -1068955.1    23877.8 -44.768  < 2e-16 ***
## Store10        628887.4   112929.0   5.569 2.71e-08 ***
## Store11       -217449.3    23756.1  -9.153  < 2e-16 ***
## Store12       -160159.8   105614.7  -1.516 0.129475    
## Store13        665390.8   114607.5   5.806 6.85e-09 ***
## Store14        541155.6    43009.0  12.582  < 2e-16 ***
## Store15       -711503.8   105846.8  -6.722 2.02e-11 ***
## Store16      -1033264.4    39281.3 -26.304  < 2e-16 ***
## Store17       -482891.3   115651.4  -4.175 3.03e-05 ***
## Store18       -236188.4   103207.7  -2.288 0.022156 *  
## Store19         88916.7   105944.5   0.839 0.401359    
## Store20        568352.9    25871.2  21.969  < 2e-16 ***
## Store21       -815160.0    22958.8 -35.505  < 2e-16 ***
## Store22       -323211.6   100196.3  -3.226 0.001265 ** 
## Store23        -29770.2   113150.0  -0.263 0.792482    
## Store24         27496.8   104872.5   0.262 0.793185    
## Store25       -847649.9    25399.5 -33.373  < 2e-16 ***
## Store26       -359445.5   105525.4  -3.406 0.000664 ***
## Store27        439229.1   101050.9   4.347 1.41e-05 ***
## Store28        139953.5   105779.4   1.323 0.185880    
## Store29       -750276.3   101676.3  -7.379 1.89e-13 ***
## Store30      -1122743.3    22425.9 -50.065  < 2e-16 ***
## Store31       -158464.1    22737.4  -6.969 3.65e-12 ***
## Store32       -332244.3    35092.7  -9.468  < 2e-16 ***
## Store33      -1023329.2   112745.7  -9.076  < 2e-16 ***
## Store34       -312719.9   107897.4  -2.898 0.003770 ** 
## Store35       -415109.3    98516.6  -4.214 2.56e-05 ***
## Store36      -1180433.3    23588.0 -50.044  < 2e-16 ***
## Store37      -1035121.3    22767.4 -45.465  < 2e-16 ***
## Store38       -796167.5   105624.2  -7.538 5.75e-14 ***
## Store39        -86778.8    23088.3  -3.759 0.000173 ***
## Store40       -455869.6   113041.5  -4.033 5.60e-05 ***
## Store41       -279251.2    37950.0  -7.358 2.20e-13 ***
## Store42       -730734.7   113110.0  -6.460 1.16e-10 ***
## Store43       -857065.6    25926.2 -33.058  < 2e-16 ***
## Store44      -1056135.9   115347.2  -9.156  < 2e-16 ***
## Store45       -676430.4    43141.6 -15.679  < 2e-16 ***
## Holiday_Flag    75352.5     9602.9   7.847 5.30e-15 ***
## Temperature      -904.9      159.4  -5.677 1.46e-08 ***
## Fuel_Price     -42007.4     8681.7  -4.839 1.35e-06 ***
## CPI              2692.5     1262.7   2.132 0.033030 *  
## Unemployment   -23933.5     5245.3  -4.563 5.18e-06 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 162300 on 4475 degrees of freedom
## Multiple R-squared:  0.9183, Adjusted R-squared:  0.9174 
## F-statistic:  1027 on 49 and 4475 DF,  p-value: < 2.2e-16

Model with interactions

## 
## Call:
## lm(formula = Weekly_Sales ~ (. - Date)^2, data = trainlm)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -595853  -56670   -9233   31098 1663498 
## 
## Coefficients:
##                             Estimate Std. Error t value Pr(>|t|)    
## (Intercept)               -1.814e+07  8.062e+06  -2.250 0.024511 *  
## Store2                    -8.331e+06  5.105e+06  -1.632 0.102745    
## Store3                     3.765e+05  4.068e+06   0.093 0.926263    
## Store4                     6.159e+06  7.469e+06   0.825 0.409655    
## Store5                     2.510e+06  4.114e+06   0.610 0.541772    
## Store6                    -1.580e+06  4.203e+06  -0.376 0.706981    
## Store7                    -6.242e+06  4.675e+06  -1.335 0.181873    
## Store8                     1.432e+06  3.929e+06   0.364 0.715508    
## Store9                     1.661e+05  4.227e+06   0.039 0.968652    
## Store10                    1.770e+07  6.886e+06   2.570 0.010201 *  
## Store11                   -2.909e+05  3.722e+06  -0.078 0.937700    
## Store12                    3.120e+06  5.194e+06   0.601 0.548010    
## Store13                    3.080e+07  9.377e+06   3.285 0.001029 ** 
## Store14                    1.252e+07  2.922e+06   4.284 1.88e-05 ***
## Store15                    8.150e+06  3.889e+06   2.095 0.036191 *  
## Store16                    1.208e+06  4.688e+06   0.258 0.796708    
## Store17                    8.361e+06  5.679e+06   1.472 0.140991    
## Store18                    6.954e+06  5.343e+06   1.301 0.193187    
## Store19                    9.525e+06  3.917e+06   2.432 0.015060 *  
## Store20                    3.499e+06  2.937e+06   1.192 0.233503    
## Store21                   -7.614e+06  5.407e+06  -1.408 0.159167    
## Store22                    9.818e+06  5.335e+06   1.840 0.065804 .  
## Store23                    1.253e+07  7.375e+06   1.699 0.089421 .  
## Store24                    7.089e+06  3.947e+06   1.796 0.072533 .  
## Store25                    3.174e+06  2.877e+06   1.103 0.270030    
## Store26                    8.832e+06  6.401e+06   1.380 0.167727    
## Store27                    9.699e+06  3.782e+06   2.564 0.010372 *  
## Store28                    5.353e+06  5.495e+06   0.974 0.330074    
## Store29                    4.681e+06  4.580e+06   1.022 0.306796    
## Store30                    4.165e+06  5.516e+06   0.755 0.450307    
## Store31                   -2.542e+06  5.151e+06  -0.493 0.621745    
## Store32                   -2.575e+06  4.584e+06  -0.562 0.574296    
## Store33                    8.365e+06  6.916e+06   1.209 0.226567    
## Store34                    8.236e+06  4.169e+06   1.975 0.048283 *  
## Store35                    8.761e+06  3.507e+06   2.498 0.012519 *  
## Store36                    7.062e+06  5.651e+06   1.250 0.211444    
## Store37                    3.599e+06  5.119e+06   0.703 0.482085    
## Store38                    4.123e+06  5.546e+06   0.743 0.457294    
## Store39                   -1.458e+07  5.140e+06  -2.836 0.004588 ** 
## Store40                    1.089e+07  7.608e+06   1.432 0.152355    
## Store41                   -5.113e+05  5.599e+06  -0.091 0.927241    
## Store42                    1.157e+07  7.260e+06   1.593 0.111151    
## Store43                    3.284e+06  3.349e+06   0.981 0.326839    
## Store44                    1.331e+07  9.283e+06   1.434 0.151653    
## Store45                    1.724e+06  3.065e+06   0.562 0.573828    
## Holiday_Flag               5.898e+05  1.229e+06   0.480 0.631282    
## Temperature                5.782e+04  2.005e+04   2.883 0.003958 ** 
## Fuel_Price                 1.940e+06  9.748e+05   1.990 0.046601 *  
## CPI                        9.192e+04  3.752e+04   2.450 0.014330 *  
## Unemployment               8.046e+05  8.959e+05   0.898 0.369154    
## Store2:Holiday_Flag       -6.298e+04  9.041e+04  -0.697 0.486094    
## Store3:Holiday_Flag       -9.216e+04  9.262e+04  -0.995 0.319760    
## Store4:Holiday_Flag       -1.427e+05  5.318e+05  -0.268 0.788436    
## Store5:Holiday_Flag       -1.316e+05  9.508e+04  -1.384 0.166313    
## Store6:Holiday_Flag       -5.437e+04  9.331e+04  -0.583 0.560107    
## Store7:Holiday_Flag        2.854e+03  1.522e+05   0.019 0.985038    
## Store8:Holiday_Flag       -1.029e+05  1.016e+05  -1.013 0.311222    
## Store9:Holiday_Flag       -1.575e+05  9.449e+04  -1.667 0.095633 .  
## Store10:Holiday_Flag      -4.117e+04  5.120e+05  -0.080 0.935918    
## Store11:Holiday_Flag      -1.514e+05  1.011e+05  -1.497 0.134419    
## Store12:Holiday_Flag       2.152e+05  4.889e+05   0.440 0.659752    
## Store13:Holiday_Flag      -3.399e+04  5.142e+05  -0.066 0.947296    
## Store14:Holiday_Flag       3.479e+04  1.921e+05   0.181 0.856301    
## Store15:Holiday_Flag      -1.332e+05  4.835e+05  -0.275 0.783029    
## Store16:Holiday_Flag      -1.200e+05  1.731e+05  -0.693 0.488480    
## Store17:Holiday_Flag      -6.268e+04  5.202e+05  -0.120 0.904095    
## Store18:Holiday_Flag       1.021e+05  4.744e+05   0.215 0.829576    
## Store19:Holiday_Flag       6.892e+04  4.810e+05   0.143 0.886067    
## Store20:Holiday_Flag      -5.090e+04  1.016e+05  -0.501 0.616558    
## Store21:Holiday_Flag      -8.772e+04  8.957e+04  -0.979 0.327420    
## Store22:Holiday_Flag      -7.716e+04  4.563e+05  -0.169 0.865740    
## Store23:Holiday_Flag      -7.343e+04  5.082e+05  -0.144 0.885121    
## Store24:Holiday_Flag       7.853e+04  4.791e+05   0.164 0.869816    
## Store25:Holiday_Flag      -3.724e+04  1.065e+05  -0.350 0.726486    
## Store26:Holiday_Flag       7.173e+03  4.818e+05   0.015 0.988123    
## Store27:Holiday_Flag       1.067e+05  4.582e+05   0.233 0.815834    
## Store28:Holiday_Flag       2.523e+05  4.899e+05   0.515 0.606670    
## Store29:Holiday_Flag       6.965e+04  4.680e+05   0.149 0.881703    
## Store30:Holiday_Flag      -1.108e+05  9.073e+04  -1.222 0.221875    
## Store31:Holiday_Flag       1.405e+03  8.970e+04   0.016 0.987506    
## Store32:Holiday_Flag      -5.212e+04  1.529e+05  -0.341 0.733298    
## Store33:Holiday_Flag      -1.330e+05  5.136e+05  -0.259 0.795731    
## Store34:Holiday_Flag       3.104e+04  4.911e+05   0.063 0.949597    
## Store35:Holiday_Flag       1.075e+05  4.488e+05   0.240 0.810666    
## Store36:Holiday_Flag      -1.031e+05  9.148e+04  -1.127 0.259926    
## Store37:Holiday_Flag      -1.230e+05  8.919e+04  -1.380 0.167809    
## Store38:Holiday_Flag       8.040e+04  4.907e+05   0.164 0.869851    
## Store39:Holiday_Flag       1.467e+04  8.953e+04   0.164 0.869811    
## Store40:Holiday_Flag      -1.706e+05  5.075e+05  -0.336 0.736710    
## Store41:Holiday_Flag      -6.340e+04  1.633e+05  -0.388 0.697848    
## Store42:Holiday_Flag      -5.911e+04  5.160e+05  -0.115 0.908803    
## Store43:Holiday_Flag      -1.034e+04  1.062e+05  -0.097 0.922422    
## Store44:Holiday_Flag      -1.780e+05  5.179e+05  -0.344 0.731127    
## Store45:Holiday_Flag      -5.190e+04  2.014e+05  -0.258 0.796624    
## Store2:Temperature        -3.422e+02  1.589e+03  -0.215 0.829459    
## Store3:Temperature         1.367e+03  1.788e+03   0.764 0.444622    
## Store4:Temperature        -2.901e+04  8.502e+03  -3.413 0.000650 ***
## Store5:Temperature         1.004e+03  1.796e+03   0.559 0.576016    
## Store6:Temperature         1.287e+03  1.644e+03   0.783 0.433843    
## Store7:Temperature        -2.781e+03  2.488e+03  -1.118 0.263621    
## Store8:Temperature        -1.247e+03  1.668e+03  -0.748 0.454675    
## Store9:Temperature         1.095e+03  1.680e+03   0.652 0.514718    
## Store10:Temperature       -3.373e+04  8.335e+03  -4.047 5.27e-05 ***
## Store11:Temperature       -2.239e+03  1.951e+03  -1.148 0.251214    
## Store12:Temperature       -2.324e+04  7.968e+03  -2.917 0.003551 ** 
## Store13:Temperature       -2.788e+04  8.417e+03  -3.313 0.000931 ***
## Store14:Temperature       -7.534e+03  3.148e+03  -2.393 0.016735 *  
## Store15:Temperature       -2.231e+04  7.775e+03  -2.869 0.004133 ** 
## Store16:Temperature       -3.202e+03  2.708e+03  -1.182 0.237079    
## Store17:Temperature       -2.320e+04  8.447e+03  -2.746 0.006055 ** 
## Store18:Temperature       -2.182e+04  7.671e+03  -2.845 0.004467 ** 
## Store19:Temperature       -2.033e+04  7.771e+03  -2.616 0.008941 ** 
## Store20:Temperature       -6.782e+03  1.744e+03  -3.889 0.000102 ***
## Store21:Temperature        1.255e+03  1.620e+03   0.774 0.438867    
## Store22:Temperature       -2.015e+04  7.391e+03  -2.726 0.006441 ** 
## Store23:Temperature       -2.249e+04  8.148e+03  -2.761 0.005795 ** 
## Store24:Temperature       -1.998e+04  7.714e+03  -2.590 0.009623 ** 
## Store25:Temperature       -8.659e+02  1.695e+03  -0.511 0.609419    
## Store26:Temperature       -1.945e+04  7.774e+03  -2.503 0.012368 *  
## Store27:Temperature       -1.708e+04  7.444e+03  -2.295 0.021780 *  
## Store28:Temperature       -2.404e+04  7.976e+03  -3.014 0.002593 ** 
## Store29:Temperature       -2.161e+04  7.557e+03  -2.860 0.004254 ** 
## Store30:Temperature        1.313e+03  1.571e+03   0.836 0.403253    
## Store31:Temperature       -1.742e+02  1.561e+03  -0.112 0.911142    
## Store32:Temperature       -3.208e+03  2.467e+03  -1.301 0.193485    
## Store33:Temperature       -2.304e+04  8.315e+03  -2.771 0.005610 ** 
## Store34:Temperature       -2.286e+04  7.973e+03  -2.868 0.004155 ** 
## Store35:Temperature       -1.777e+04  7.258e+03  -2.449 0.014380 *  
## Store36:Temperature        1.871e+03  1.846e+03   1.013 0.310967    
## Store37:Temperature        6.751e+02  1.887e+03   0.358 0.720565    
## Store38:Temperature       -2.042e+04  7.966e+03  -2.563 0.010417 *  
## Store39:Temperature        2.146e+03  1.859e+03   1.154 0.248437    
## Store40:Temperature       -2.277e+04  8.144e+03  -2.796 0.005205 ** 
## Store41:Temperature       -3.442e+03  2.626e+03  -1.311 0.190021    
## Store42:Temperature       -2.449e+04  8.350e+03  -2.933 0.003375 ** 
## Store43:Temperature        1.737e+03  1.876e+03   0.926 0.354702    
## Store44:Temperature       -2.378e+04  8.441e+03  -2.817 0.004874 ** 
## Store45:Temperature       -8.208e+03  3.146e+03  -2.609 0.009117 ** 
## Store2:Fuel_Price         -2.059e+05  9.131e+04  -2.254 0.024216 *  
## Store3:Fuel_Price          5.882e+04  1.076e+05   0.547 0.584670    
## Store4:Fuel_Price         -8.848e+05  3.750e+05  -2.359 0.018349 *  
## Store5:Fuel_Price          5.886e+04  9.816e+04   0.600 0.548748    
## Store6:Fuel_Price         -3.611e+04  9.315e+04  -0.388 0.698308    
## Store7:Fuel_Price         -1.687e+05  1.208e+05  -1.397 0.162473    
## Store8:Fuel_Price          7.439e+04  1.001e+05   0.743 0.457445    
## Store9:Fuel_Price          7.942e+04  9.941e+04   0.799 0.424402    
## Store10:Fuel_Price        -8.946e+05  3.527e+05  -2.537 0.011227 *  
## Store11:Fuel_Price         1.153e+03  1.045e+05   0.011 0.991198    
## Store12:Fuel_Price        -8.630e+05  3.271e+05  -2.638 0.008366 ** 
## Store13:Fuel_Price        -6.703e+05  3.762e+05  -1.782 0.074881 .  
## Store14:Fuel_Price        -2.311e+05  1.418e+05  -1.630 0.103259    
## Store15:Fuel_Price        -7.849e+05  3.362e+05  -2.335 0.019599 *  
## Store16:Fuel_Price        -1.252e+05  1.498e+05  -0.836 0.403408    
## Store17:Fuel_Price        -7.646e+05  3.799e+05  -2.013 0.044215 *  
## Store18:Fuel_Price        -8.899e+05  3.246e+05  -2.741 0.006145 ** 
## Store19:Fuel_Price        -7.829e+05  3.354e+05  -2.334 0.019626 *  
## Store20:Fuel_Price        -7.169e+04  1.008e+05  -0.711 0.477062    
## Store21:Fuel_Price        -3.853e+04  9.499e+04  -0.406 0.685019    
## Store22:Fuel_Price        -7.208e+05  3.181e+05  -2.266 0.023525 *  
## Store23:Fuel_Price        -7.726e+05  3.743e+05  -2.064 0.039041 *  
## Store24:Fuel_Price        -8.527e+05  3.315e+05  -2.572 0.010145 *  
## Store25:Fuel_Price        -5.260e+04  9.616e+04  -0.547 0.584389    
## Store26:Fuel_Price        -7.797e+05  3.361e+05  -2.319 0.020419 *  
## Store27:Fuel_Price        -8.610e+05  3.201e+05  -2.690 0.007180 ** 
## Store28:Fuel_Price        -9.208e+05  3.272e+05  -2.814 0.004908 ** 
## Store29:Fuel_Price        -8.172e+05  3.144e+05  -2.600 0.009366 ** 
## Store30:Fuel_Price         4.174e+04  9.389e+04   0.445 0.656662    
## Store31:Fuel_Price         3.539e+04  9.159e+04   0.386 0.699226    
## Store32:Fuel_Price        -1.293e+05  1.192e+05  -1.085 0.278162    
## Store33:Fuel_Price        -8.203e+05  3.521e+05  -2.330 0.019868 *  
## Store34:Fuel_Price        -8.139e+05  3.385e+05  -2.404 0.016245 *  
## Store35:Fuel_Price        -6.846e+05  3.127e+05  -2.189 0.028643 *  
## Store36:Fuel_Price         5.524e+04  1.020e+05   0.542 0.588124    
## Store37:Fuel_Price         6.730e+04  9.923e+04   0.678 0.497685    
## Store38:Fuel_Price        -8.276e+05  3.280e+05  -2.523 0.011672 *  
## Store39:Fuel_Price        -1.944e+05  9.995e+04  -1.945 0.051816 .  
## Store40:Fuel_Price        -7.718e+05  3.729e+05  -2.070 0.038551 *  
## Store41:Fuel_Price        -1.438e+05  1.362e+05  -1.056 0.291110    
## Store42:Fuel_Price        -7.562e+05  3.541e+05  -2.136 0.032759 *  
## Store43:Fuel_Price        -1.170e+04  1.171e+05  -0.100 0.920464    
## Store44:Fuel_Price        -7.429e+05  3.805e+05  -1.952 0.050960 .  
## Store45:Fuel_Price        -2.830e+05  1.450e+05  -1.952 0.050994 .  
## Store2:CPI                 3.688e+04  2.024e+04   1.822 0.068475 .  
## Store3:CPI                -7.412e+03  1.624e+04  -0.456 0.648055    
## Store4:CPI                 2.624e+04  4.374e+04   0.600 0.548500    
## Store5:CPI                -1.609e+04  1.631e+04  -0.986 0.324195    
## Store6:CPI                 5.210e+03  1.689e+04   0.308 0.757798    
## Store7:CPI                 2.733e+04  1.910e+04   1.431 0.152523    
## Store8:CPI                -1.058e+04  1.598e+04  -0.662 0.507894    
## Store9:CPI                -7.305e+03  1.717e+04  -0.426 0.670458    
## Store10:CPI               -5.707e+04  4.366e+04  -1.307 0.191258    
## Store11:CPI                4.976e+02  1.485e+04   0.034 0.973267    
## Store12:CPI                3.336e+04  4.353e+04   0.766 0.443464    
## Store13:CPI               -1.583e+05  6.233e+04  -2.539 0.011148 *  
## Store14:CPI               -4.655e+04  1.176e+04  -3.960 7.62e-05 ***
## Store15:CPI               -1.025e+04  1.728e+04  -0.593 0.553195    
## Store16:CPI               -6.055e+03  1.734e+04  -0.349 0.727012    
## Store17:CPI               -6.740e+03  2.757e+04  -0.245 0.806851    
## Store18:CPI                3.141e+03  2.828e+04   0.111 0.911564    
## Store19:CPI               -1.499e+04  1.734e+04  -0.864 0.387380    
## Store20:CPI               -5.219e+03  1.166e+04  -0.448 0.654367    
## Store21:CPI                2.478e+04  2.146e+04   1.154 0.248416    
## Store22:CPI               -1.878e+04  2.584e+04  -0.727 0.467536    
## Store23:CPI               -3.343e+04  3.696e+04  -0.904 0.365844    
## Store24:CPI                2.776e+03  2.303e+04   0.121 0.904090    
## Store25:CPI               -1.357e+04  1.121e+04  -1.210 0.226193    
## Store26:CPI               -1.067e+04  2.930e+04  -0.364 0.715677    
## Store27:CPI                1.328e+03  1.825e+04   0.073 0.942004    
## Store28:CPI                2.206e+04  4.526e+04   0.488 0.625925    
## Store29:CPI                1.314e+04  2.519e+04   0.521 0.602100    
## Store30:CPI               -2.168e+04  2.195e+04  -0.988 0.323342    
## Store31:CPI                8.565e+03  2.039e+04   0.420 0.674404    
## Store32:CPI                1.246e+04  1.866e+04   0.668 0.504277    
## Store33:CPI               -1.223e+04  4.423e+04  -0.277 0.782172    
## Store34:CPI               -5.265e+03  2.446e+04  -0.215 0.829578    
## Store35:CPI               -4.556e+04  1.572e+04  -2.898 0.003772 ** 
## Store36:CPI               -3.577e+04  2.328e+04  -1.536 0.124498    
## Store37:CPI               -1.929e+04  2.094e+04  -0.921 0.357078    
## Store38:CPI                2.079e+04  4.613e+04   0.451 0.652188    
## Store39:CPI                6.311e+04  2.102e+04   3.003 0.002691 ** 
## Store40:CPI               -2.548e+04  3.894e+04  -0.654 0.512993    
## Store41:CPI                1.030e+04  2.152e+04   0.478 0.632354    
## Store42:CPI               -3.252e+04  4.623e+04  -0.704 0.481732    
## Store43:CPI               -1.396e+04  1.571e+04  -0.888 0.374546    
## Store44:CPI               -4.823e+04  6.132e+04  -0.787 0.431597    
## Store45:CPI               -1.242e+03  1.242e+04  -0.100 0.920353    
## Store2:Unemployment        1.864e+05  1.287e+05   1.449 0.147481    
## Store3:Unemployment       -3.037e+04  1.183e+05  -0.257 0.797327    
## Store4:Unemployment       -3.970e+05  3.966e+05  -1.001 0.316892    
## Store5:Unemployment       -7.319e+04  1.329e+05  -0.551 0.581842    
## Store6:Unemployment        7.442e+04  1.197e+05   0.622 0.534185    
## Store7:Unemployment        1.055e+05  1.695e+05   0.622 0.533826    
## Store8:Unemployment        1.655e+04  1.282e+05   0.129 0.897298    
## Store9:Unemployment        1.826e+04  1.282e+05   0.142 0.886743    
## Store10:Unemployment      -4.471e+05  4.030e+05  -1.109 0.267314    
## Store11:Unemployment       1.818e+04  1.108e+05   0.164 0.869630    
## Store12:Unemployment      -3.227e+05  3.994e+05  -0.808 0.419130    
## Store13:Unemployment      -6.448e+05  4.048e+05  -1.593 0.111318    
## Store14:Unemployment      -2.179e+05  2.224e+05  -0.980 0.327117    
## Store15:Unemployment      -3.235e+05  3.896e+05  -0.830 0.406368    
## Store16:Unemployment       9.924e+03  2.102e+05   0.047 0.962354    
## Store17:Unemployment      -3.783e+05  4.033e+05  -0.938 0.348287    
## Store18:Unemployment      -3.073e+05  3.833e+05  -0.802 0.422848    
## Store19:Unemployment      -3.305e+05  3.899e+05  -0.848 0.396660    
## Store20:Unemployment      -1.476e+05  1.247e+05  -1.184 0.236418    
## Store21:Unemployment       1.970e+05  1.348e+05   1.461 0.143975    
## Store22:Unemployment      -3.797e+05  3.730e+05  -1.018 0.308816    
## Store23:Unemployment      -4.261e+05  4.055e+05  -1.051 0.293313    
## Store24:Unemployment      -3.083e+05  3.841e+05  -0.803 0.422236    
## Store25:Unemployment      -1.124e+05  1.204e+05  -0.933 0.350724    
## Store26:Unemployment      -3.772e+05  4.177e+05  -0.903 0.366554    
## Store27:Unemployment      -5.802e+05  3.753e+05  -1.546 0.122159    
## Store28:Unemployment      -3.391e+05  3.995e+05  -0.849 0.395959    
## Store29:Unemployment      -2.968e+05  3.782e+05  -0.785 0.432601    
## Store30:Unemployment      -1.088e+05  1.354e+05  -0.804 0.421387    
## Store31:Unemployment       5.690e+04  1.303e+05   0.437 0.662380    
## Store32:Unemployment       6.996e+04  1.699e+05   0.412 0.680477    
## Store33:Unemployment      -3.428e+05  4.027e+05  -0.851 0.394789    
## Store34:Unemployment      -3.548e+05  3.965e+05  -0.895 0.370974    
## Store35:Unemployment       1.251e+05  3.743e+05   0.334 0.738222    
## Store36:Unemployment      -1.108e+05  1.217e+05  -0.910 0.362673    
## Store37:Unemployment      -9.578e+04  1.147e+05  -0.835 0.403602    
## Store38:Unemployment      -3.481e+05  3.992e+05  -0.872 0.383256    
## Store39:Unemployment       1.783e+05  1.167e+05   1.528 0.126469    
## Store40:Unemployment      -3.931e+05  4.087e+05  -0.962 0.336210    
## Store41:Unemployment      -9.309e+04  2.170e+05  -0.429 0.667978    
## Store42:Unemployment      -3.934e+05  4.055e+05  -0.970 0.332042    
## Store43:Unemployment      -1.481e+05  9.918e+04  -1.493 0.135427    
## Store44:Unemployment      -4.131e+05  4.045e+05  -1.021 0.307146    
## Store45:Unemployment      -6.143e+04  2.234e+05  -0.275 0.783374    
## Holiday_Flag:Temperature   1.680e+03  5.993e+02   2.803 0.005089 ** 
## Holiday_Flag:Fuel_Price   -4.141e+04  4.670e+04  -0.887 0.375264    
## Holiday_Flag:CPI          -6.259e+02  5.717e+03  -0.109 0.912830    
## Holiday_Flag:Unemployment -4.157e+04  2.359e+04  -1.763 0.078039 .  
## Temperature:Fuel_Price     2.144e+03  6.999e+02   3.064 0.002200 ** 
## Temperature:CPI           -2.865e+02  9.339e+01  -3.068 0.002169 ** 
## Temperature:Unemployment  -6.384e+02  3.686e+02  -1.732 0.083361 .  
## Fuel_Price:CPI            -1.013e+04  4.026e+03  -2.516 0.011910 *  
## Fuel_Price:Unemployment    3.937e+03  2.348e+04   0.168 0.866853    
## CPI:Unemployment          -3.307e+03  4.262e+03  -0.776 0.437856    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 154000 on 4245 degrees of freedom
## Multiple R-squared:  0.9303, Adjusted R-squared:  0.9257 
## F-statistic:   203 on 279 and 4245 DF,  p-value: < 2.2e-16