Table 3 Results of the feature selection based on stepwise regression model regarding the grain yield as response variable for normal irrigation and drought stress conditions
Normal irrigation | ||||||
 Entered Variable |  | Removed variable | Partial R2 | Model R2 | F Value | p > F |
 Protein |  | aNA | 0.89 | 0.89 | 1395.98 | 0.017 |
Over all ANOVA of the final model of selected variables | ||||||
 Source |  | DF | Sum of squares | Mean Square | F Value | p > F |
 Model |  | 1 | 881.368 | 881.36 | 52.67 | <.0001 |
 Error |  | 538 | 9002.63 | 16.73 | NA | NA |
Parameter estimation for the final model of selected variables | ||||||
 Variable | Parameter | Standard parameter | Standard error | Sum of squares | F Value | p > F |
 Intercept | 1030.13 | NA | 4.12948 | 39,289 | 62,229.6 | 0.003 |
 Protein | −27.7947 | −2.40241 | 0.74391 | 881.36 | 1395.98 | 0.017 |
Drought stress | ||||||
 Entered Variable |  | Removed variable | Partial R2 | Model R2 | F Value | p > F |
 SOD |  | NA | 0.520 | 0.5195 | 73.02 | <.0001 |
 Proline |  | NA | 0.244 | 0.7635 | 28.23 | <.0001 |
 GR |  | NA | 0.042 | 0.8055 | 2.710 | 0. 003 |
Over all ANOVA of the final model of selected variables | ||||||
 Source |  | DF | Sum of squares | Mean Square | F Value | p > F |
 Model |  | 3 | 2,380,092.0 | 793,364 | 35.99 | <.0001 |
 Error |  | 536 | 11,813,999 | 22,041.0 | NA | NA |
Parameter estimation for the final model of selected variables | ||||||
 Variable | Parameter | Standard parameter | Standard error | Sum of squares | F Value | p > F |
 Intercept | 821.479 | NA | 40.6503 | 9,001,165 | 408.4 | <.0001 |
 Proline | −4.14588 | −0.173164 | 2.51802 | 59,751.00 | 2.710 | 0.030 |
 SOD | 4.65863 | 0.347539 | 0.86511 | 639,160.0 | 29.00 | <.0001 |
 GR | −8.43598 | −0.102254 | 0.84753 | 2,183,721 | 99.08 | <.0001 |