Suppose the starting point for model selection for the birth weight data were the full model, with all variables. The table below shows the adjusted \(R^{2}\) for the full model as well as the adjusted \(R^{2}\) values for all models with one fewer predictor variable. Based on examining the table from Exercise 7.5 and the following table, identify which variable, if any, should be removed from the model first. Explain your answer.

Data From Exercise 7.5

Data From Exercise 7.3

Model Adjusted R2 1 Full model 0.2541 2 No gestation 0.1031 3 No parity 0.2492 4 No age 0.2547 5 No height 0.2311 6 No weight 0.2536 7 No smoking status 0.2072