10 let us consider the following validation data set confusion matrix is the result of a logistic regression model which includes if the patient will have a heart attack as a dependent variable which is connected to the range of independent variables. In this model y=1 indicates heart attack and y=0 indicates not having a heart attack. Cutoff value is considered 50 per cent. a) Calculate sensitivity, specificity and overall error of the model. b) Considering this confusion matrix do you think shall we make a change in the cutoff value? Justify your answer. Predicted class 1 ll 1 270 0 1000 Actual class 0 ' 70 3068