Fitting Ordinary Least Squares Model

At first, an OLS model is investigated, summary output table is printed below:

EstimateStd. Errort valuePr(> |t|)
(Intercept)10739.3519323.281233.220.0000
AREA_SQ_M0.01020.00254.040.0001
HUBDISTBUS-1.56660.9151-1.710.0870
HUBDISTMET-1.14450.1295-8.840.0000
HUBDISTTRA-0.07380.1357-0.540.5867
HUBDISTTRAM-0.43520.1164-3.740.0002
ScoresF:65.78 (5,2302)M. R^2: 0.125Adj. R^2: 0.1231AIC: 46814.1

With p value above 0.05, it can be concluded that bus and tram distance are not significant. This is most likely to be caused by multicolinearity of independent variables as all predictors are related with distance and even have the same unit. A model reduction is performed to have only significant variables. Summary table of the reduced model is printed below:

EstimateStd. Errort valuePr(>|t|)
(Intercept)10304.5593210.620148.920.0000
AREA_SQ_M0.01010.00254.020.0001
HUBDISTMET-1.15070.1283-8.970.0000
HUBDISTTRAM-0.44000.1149-3.830.0001
ScoresF:108.4 (3,2302)M. R^2: 0.1237Adj. R^2: 0.1226AIC: 46813.49

Adjusted R squared metrics of the reduced model is 0.1226. It can be concluded that 12.26 percent of the variance in the data can be explained. Although model reduction was performed and model performance has slightly increased the model still fits poorly to the data.

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