In: Math
Gautam is interested in learning what types of ethical messages are most effective.
He has three conditions, integrity, confidentiality, professional behavio, and
he randomly assigns 20 people to each of these conditions. After each person reads the message, they rate its effectiveness
on a 1-10 scale.He runs a one-way ANOVA and finds the following results:
Condition Mean
Integrity 6
Confidentiality 5
Professional Behavior 9
Source SS df MS F
Between 3000 2
Within
Total 11,500 59
a)Complete the one-way ANOVA table.
b) Determine the critical F at a=.01
What conclusion should Gautam make?
c) Is it appropriate to calculate a Tukey HSD test for this problem? Why? If it is appropriate, calculate a Tukey HSD test for each of the three possible comparisons between two means. What groups are significantly different from each other at a=.01
(integrity, confidentiality, professional behavior) according to this test?
a)
ANOVA | ||||||
Source of Variation | SS | df | MS | F | P-value | F crit |
Between Groups | 3000 | 2 | 1500.0000 | 10.0588 | 0.0002 | 4.9981 |
Within Groups | 8500 | 57 | 149.1228 | |||
Total | 11500 | 59 | ||||
Level of significance | 0.01 |
b)
f-critical = 4.9981 < f-stat=10.0588,so null hypothesi rejected that all means are equal
c)
yes,it is appropriate as null hypothesi is rejcted
MSwithin=149.1228
std error of difference = sqrt [MSwithin / 2 (1/ni+1/nj)]
q(2,57,0.01)=3.7687
CR=q*std error
if abs difference>CR,means are different ,otherwise not
Sample | Sample | Absolute | Std. Error | Critical | ||||
Group | Mean | Size | Comparison | Difference | of Difference | Range | Results | |
integrity | 6 | 20 | Group 1 to Group 2 | 1 | 2.730593406 | 10.29078737 | Means are not different | |
Confidentiality | 5 | 20 | Group 1 to Group 3 | 3 | 2.730593406 | 10.29078737 | Means are not different | |
professional | 9 | 20 | Group 2 to Group 3 | 4 | 2.730593406 | 10.29078737 | Means are not different | |
Other Data | ||||||||
Level of significance | 0.01 | |||||||
Numerator d.f. | 2 | |||||||
Denominator d.f. | 57 | |||||||
MSW | 149.122807 | |||||||
Q Statistic | 3.7687 |