Question

An experimental psychologist plans a study in which a crucial step is offering participants a food reward. It is important that the three food rewards be equal in appeal. Thus, a prestudy was designed in which participants were asked which of the rewards they preferred. Of the 60 participants, 16 preferred cupcakes, 26 preferred candy bars, and 18 favored dried apricots. Do these scores suggest that the different foods are differentially preferred by people in general? (Use the .05 significance level.)

Use the five steps of hypothesis testing.

Answer 1

observed frequencey, O	expected proportion	expected frequency,E	(O-E)		(O-E)²/E
16	0.333	20.00	-4.00		0.800
26	0.333	20.00	6.00		1.800
18	0.333	20.00	-2.00		0.200

1) Ho:  different foods are equally preferred by people in general

2) Ha:  different foods are differentially preferred by people in general

3) chi square test statistic,X² = Σ(O-E)²/E =   2.800

4)

Degree of freedom=k-1=   3   -   1   =   2
                  
P value =   0.2466   [ excel function: =chisq.dist.rt(test-stat,df) ]          

5) there is no evidence to conlcude that  different foods are differentially preferred by people in general