2. A software quality engineer wants to develop a regression model for predicting the number of faults in program (y). S/He decided that three software complexity metrics are potentially useful as indepen- dent variables, namely program size in lines of code in program (), program control flow measured in terms of the number of branches (x2) and the number of tokens in program (23). Data were collected on a set of 24 programs from a distributed application in a data com- munication software system. The ANOVA table for the model yi = Bo + B11i + 2x2i + B3X3i + 6i was found to be as follows: = MS Source of Variation df SS 5409.89 Model 3 20 16.35 23 5426.24 Error Total (a) Test to determine whether a regression relation exists between y and the set of independent variables. Use a level of significance of .05. What do you find? (b) Does the conclusion that a regression relation exists imply that the software quality engineer need not screen the independent vari- ables and can just use them all? If a regression relation had not existed, what would this imply about screening the independent variables?