Omar is a school superintendent who is trying to improve the selection process for teachers in his school district. Before implementing the selection test as a deciding factor in the hiring process, Omar decides to give the test to current teachers to see if the test can accurately differentiate the top performers from the mediocre and poor performers. Which term below best describes Omar's strategy in this case? a. Test reliability method b. Test-retest validation c. Concurrent validation d. Criterion-related validation

An important application of regression analysis in accounting is in the estimation of cost. by collecting data on volume and cost and using the least squares method to develop an estimated regression equation relating volume and cost, an accountant can estimate the cost associated with a particular manufacturing volume. consider the following sample of production volumes and total cost data for a manufacturing operation. production volume (units) total cost ($) 400 4000 450 5000 550 5400 600 5900 700 6400 750 7000 compute b 1 and b 0 (to 2 decimals if necessary). b 1 b 0 complete the estimated regression equation (to 2 decimals if necessary). = + x what is the variable cost per unit produced (to 1 decimal)? $ compute the coefficient of determination (to 4 decimals). note: report r 2 between 0 and 1. r 2 = what percentage of the variation in total cost can be explained by the production volume (to 2 decimals)? % the company's production schedule shows 500 units must be produced next month. what is the estimated total cost for this operation (to 2 decimals)? $