Question

apply statistical methods and analysis. Unless otherwise stated, use 5% (.05) as your alpha level (cutoff for statistical significance).

Ice Cream Flavor Preference by Gender
	Men	Women	Marginal Row Totals
Vanilla	15	10	25
Chocolate	30	5	35
Marginal Column Totals	45	15	60    (Grand Total)

The chi-square statistic is 5.143. The p-value is .0233. This result is significant at p < .05.
#1. The chart above shows male and female preferences for vanilla vs. chocolate ice cream among men and women.

1. What percent of men prefer chocolate over vanilla? ________
2. What percent of women prefer chocolate over vanilla? ________
3. Report the results of the statistical test in plain language:

#2. The calculator at this link will allow you to perform a one-way chi-square or “goodness of fit test”:
http://vassarstats.net/csfit.html

Fifty students can choose between four different professors to take Introductory Statistics. The number choosing each professor is shown below. Use the calculator above to test the null hypothesis that there is no preference for professors -- that there is an equal chance of choosing each of them. Report your results including chi-square, degrees of freedom, p-value and your interpretation. Use an alpha level of .05. Be careful not to over interpret – state only what the test result tells you.

Professor	N
Dr. Able	20
Dr. Baker	8
Dr. Chavez	14
Dr. Davis	8

#3. Match these non-parametric statistical tests with their parametric counterpart by putting the corresponding letter on the line.
_____ Friedman test
_____ Kruskal-Wallis H test
_____ Mann-Whitney U test
_____ Wilcoxon Signed-Ranks T test

A: Paired-sample t-test
B: Independent-sample t-test
C: One-way ANOVA, independent samples
D: One-way ANOVA, repeated measures

Answer 1

Solution:

1. a. To find what percent of men prefer chocolate over vennila we need to use the following percentage formula

Y/X = P%

X- chocolate Y- vennila

15/30 = 0.5*100 = 50%

Therefore 50% of men prefer chocolate over vennila.

b. Similarly to find what percent of women prefer chocolate over vennila is given as

10/5= 2*100 = 200%

Therefore twice the hundred of women prefer chocolate over vennila

2. From the given date the chi-square test is performed which is given as follows

chi square calculated value is 7.92

Chi square table value for alpha = 0.05 for 4 df is 9.488

Since calculated value is less than the table value it is not significant and null hypothesis is accepted at 5% level of significance. Hence we conclude that no preference for professors -- that there is equal chance for choosing each of them.

3. One way ANOVA, repeated measures - Friedman test

One way ANOVA, independent samples - Kruskal-Wallis H test

Paired sample t-test - Mann Whitney U test

Independent sample t-test - Wilcoxon Signed Rank T test