PROBLEM STATEMENT 4 Suppose that a fast-food chain having four branches in a certain geographical area wants to evaluate the service at these restaurants. The customer services director for the chain hires 24 investigators with varied experiences in food-service evaluations to act as raters. After preliminary consultations, the 24 investigators are stratified into six blocks of four-based on food service evaluation experience-so that the four most experienced investigators are placed in block | 1, the next four most experienced investigators are placed in block 2, and so on. Within each of the six homogenous blocks, the four raters are then randomly assigned to evaluate the service at a particular restaurant using a rating scale from 0 (low) to 100 (high). The results are summarized in the table shown below. RESTAURANTS B BLOCKS OF A C D RATERS 1 70 61 82 74 2 3 77 76 75 67 88 90 76 80 80 84 63 66 96 92 76 84 4 5 78 68 98 86 Use a 0.01 level of significance to test the hypothesis that (a) service performance of the four restaurants are equal; (b) there is no significant differences among the raters. HYPOTHESIS The rating of the investigators in the four restaurants are being compared in terms of two factors: • Differences in the rating of the raters (investigators) • Differences in the food-service performance of the restaurants Thus, the hypotheses are: Ho: На: Но: |На: Test at a= 0.01 Critical Region: F1 > F;> at vi = at vi = v2 = V2 =