The following simple model is used to determine the annual savings of an individual on the basis of his annual income and education. Savings = β 0 +∂ 0 Edu + β 1 Inc+u The variable ‘Edu’ takes a value of 1 if the person is educated and the variable ‘Inc’ measures the income of the individual. Refer to the model above. The inclusion of another binary variable in this model that takes a value of 1 if a person is uneducated, will give rise to the problem of _____.