In: Statistics and Probability
Proficiency of math courses is evaluated using a special
departmental assessment. Three different instructors at two
different class times are assessed. The data are below. What can
the department conclude with an α of 0.01?
| 1 | 2 | ||||
| A | B | C | A | B | C | 
| 100 88 96 98  | 
85 79 80 90  | 
89 95 89 61  | 
94 81 80 85  | 
72 63 73 77  | 
88 94 96 87  | 
b) Obtain/compute the appropriate values to make a
decision about H0.
Time: critical value =   ; test
statistic =  
Decision:  ---Select--- Reject H0 Fail to reject H0
Instructor: critical value =   ;
test statistic =  
Decision:  ---Select--- Reject H0 Fail to reject H0
Interaction: critical value =   ;
test statistic =  
Decision:  ---Select--- Reject H0 Fail to reject H0
c) Compute the corresponding effect size(s) and
indicate magnitude(s).
Time: η2
=   ;  ---Select--- na trivial effect
small effect medium effect large effect
Instructor: η2
=   ;  ---Select--- na trivial effect
small effect medium effect large effect
Interaction: η2
=   ;  ---Select--- na trivial effect
small effect medium effect large effect
DATA:
| A | B | C | |
| 1 | 100 | 85 | 89 | 
| 88 | 79 | 95 | |
| 96 | 80 | 89 | |
| 98 | 90 | 61 | |
| 2 | 94 | 72 | 88 | 
| 81 | 63 | 94 | |
| 80 | 73 | 96 | |
| 85 | 77 | 87 | 
..........
| Anova: Two-Factor With Replication | ||||
| SUMMARY | A | B | C | Total | 
| 1 | ||||
| Count | 4 | 4 | 4 | 12 | 
| Sum | 382 | 334 | 334 | 1050 | 
| Average | 95.5 | 83.5 | 83.5 | 87.5 | 
| Variance | 27.66667 | 25.66667 | 233 | 113 | 
| 2 | ||||
| Count | 4 | 4 | 4 | 12 | 
| Sum | 340 | 285 | 365 | 990 | 
| Average | 85 | 71.25 | 91.25 | 82.5 | 
| Variance | 40.66667 | 34.91667 | 19.58333 | 102.0909 | 
| Total | ||||
| Count | 8 | 8 | 8 | |
| Sum | 722 | 619 | 699 | |
| Average | 90.25 | 77.375 | 87.375 | |
| Variance | 60.78571 | 68.83929 | 125.4107 | 
| ANOVA | ||||||
| Source of Variation | SS | df | MS | F | P-value | F crit | 
| Sample | 150 | 1 | 150 | 2.3591 | 0.1419 | 8.2854 | 
| Columns | 730.75 | 2 | 365.375 | 5.7464 | 0.0117 | 6.0129 | 
| Interaction | 490.75 | 2 | 245.375 | 3.8591 | 0.0403 | 6.0129 | 
| Within | 1144.5 | 18 | 63.58333 | |||
| Total | 2516 | 23 | 
b)
Time: critical value = 8.2854  ; test
statistic =  2.3591
Decision: Fail to reject H0
Instructor: critical value =  6.0129 ;
test statistic =  5.7464
Decision: Fail to reject H0
Interaction: critical value = 6.0129  ;
test statistic =  3.8591
Decision: Fail to reject H0
.................
C)
Time: η2 =0.06 SMALL
Instructor: η2 =0.29 MEDIUM
Interaction: η2 = 0.19 SMALL
.............
THANKS
PLEASE UPVOTE