Question

In this study, participants were randomly assigned to one of two situations – “stress” or “no stress”. They were then put into their assigned fictitious situation and after an hour, were asked to provide an appetite score (Likert-rating). The following data are appetite scores (with higher indicating more of an appetite / i.e. the person is hungry) from 24 participants. Assume data meets all assumptions for a parametric test. Using the information provided, create an SPSS data file and conduct the appropriate statistical test to determine whether there is a statistically significant difference in appetite scores between the stress and no stress groups. Answer the following questions based on your analyses. Stress No stress 7.0 3.1 6.5 6.6 5.4 6.3 6.3 5.1 6.7 4.8 3.8 2.8 5.5 6.1 1.8 6.3 2.9 3.4 6.9 5.9 6.3 6.5 6.1 3.8

Answer 1

We have used R software to answer the question

the R code is

D=c(7.0,3.1,6.5,6.6,5.4,6.3,6.3,5.1,6.7,4.8,3.8,2.8,5.5,6.1,1.8,6.3,2.9,3.4,6.9,5.9,6.3,6.5,6.1,3.8)
length(D)
stress=D[seq(1,24,2)]
nostress=D[seq(2,24,2)]
t.test(stress,nostress,var.equal = T)

so stress samples are

7.0 6.5 5.4 6.3 6.7 3.8 5.5 1.8 2.9 6.9 6.3 6.1

no stress samples are

3.1 6.6 6.3 5.1 4.8 2.8 6.1 6.3 3.4 5.9 6.5 3.8

now we setup hypothesis that

H0: mean(stress) = mean (no stress)

vs

H0: mean(stress) mean (no stress)

then we did two sample t-test for this the outcome is

we can see that p-value = 0.5646 > 0.05 significance level,

hence we can accept H0 and can comment that the two samples has same mean