Share
Explore BrainMass

# Hypotheses Test

? HT means perform hypotheses test.

1) *HT* Four professors teach a certain class at a local college. Are the grades for that class independent of the professor who is teaching the class? Use a 2.5% level of significance.

Prof 1 Prof 2 Prof 3 Prof 4
A 35 40 35 40
B 75 45 55 45
C 65 65 80 50
D 45 60 50 65
F 40 40 30 40

3. To save you time, I am summarizing the data for you:

Sample A Sample B
n = 25 16
&#931;x = 14825 9296
&#931;(x-xbar)² = 16590 5015
s² = 691.25 334.3333333
s = 26.29163365 18.2847842

*HT* Is the mean of population A greater than the mean of population B at the 5% level of significance? HINT: Since the samples are small, you must first determine whether the two population variances are equal so that you will know which formula (pooled standard deviation or not) to use for your hypothesis test.

2) *HT* Eight sixth-grade boys are ranked by their teacher in two subjects, math and English. Test whether there is negative correlation between math skill and English skill using Spearman's rank correlation coefficient and &#945; = 2.5%.

English Math
Student Rank Rank
Andy 1 7
Ben 2 8