Question

Research Scenario: A developmental psychologist wants to study the effect of instructional type on learning of the alphabet. She randomly selects a sample of 20 students at the local preschool and assigns them to two groups, a “Testing Effect” group who takes daily tests of recall on the alphabet (n=10) and a “Meaningful to Self” group who comes up with things they like that start with each letter of the alphabet and discuss them in groups (n=10). After one week of daily sessions, all of the children are asked to recite the alphabet. The number of correctly recalled letters for each group are presented below. Create your SPSS data file (remember that there will be a grouping variable for instructional type and your second variable entered into SPSS will be your dependent variable, recall. Look at the example file from this week’s presentation if you want a visual reminder). Conduct an independent-samples t test to determine whether the instructional types resulted in a difference in recall of the alphabet.

Testing_Effect	Meaningful_to_Self
20	13
17	18
16	20
9	24
22	22
23	14
19	17
18	18
10	21
12	15

Paste the appropriate SPSS output. (3 pts)

Paste appropriate SPSS graph.    (3 pts)

Calculate the effect size given the SPSS output. Show all of your work.

Write an APA-style Results section based on your analyses. Remember to use complete sentences, include the statistical notation, and include a decision about the null hypothesis. If the results are significant, include the effect size and its interpretation as well. (4 pts)

I am stuck I created my SPSS file, I label the files testing effects and meaningful to self, however, what information do i input in the values boxes

Answer 1

This is indepedent t test.

So for this test assumption of Equal variances must satisfied. We can see in above table P value for levene's test for homogeneity of variance is 0.329 which is greater than 0.05 level of significance. Hence we fail to reject null hypothesis and conclude that variances are equal.

Now test statistic= -0.838

degrees of freedom= n1+n2-2= 18

P value= 0.413

Since P value >0.05 hence it is not significant. We therefore fail to reject null hypothesis and conclude that we do not have sufficient evidence to show that the instructional types resulted in a difference in recall of the alphabet.

Effect size= Cohen's d = (18.2 - 16.6) ⁄ 4.268746 = 0.374817. which is in between smaller and medium.

NOTE: HERE I ATTACHED THE OUTPUT OF SPSS STEP BY STEP.