Assignment:
Q1 The following hypotheses are given:
H0: σ21 = σ22
H1: σ21 ≠ σ22
A random sample of eight observations from the first population resulted in a standard deviation of 10.
A random sample of six observations from the second population resulted in a standard deviation of 7.
At the .02 significance level, is there a difference in he variation of the two populaions?
Q2 Given the flollowing sample information, test the hypothesis that the treatment means are equal at the .05 significance level.
Treatment1 Treatment 2 Treatment 3
8 3 3
11 2 4
10 1 5
3 4
2
a. State the null hypothesis and the alternate hypothesis.
b. What is the decision rule?
c. Compute SST, SSE, and SS total
d. Complete an ANOVA table
e. State your decision regarding the null hypothesis.
f. if H0 is rejected, can we conlude that treatment 1 and 2 differ? Use the 95 percet level of confidence.
Q3 The city council of Pine Bluffs is considering increasing the number of police in an effort to reduce crime. Before making a final decision, the council asks the Chief of Police to survey other cites of similar size to determine the relationship between the nuber of police and the number of crimes reported.
The Chief gathered the following sample information.
City Police # of Crimes City Police # of Crimes
Oxford 15 17 Holgate 17 7
Starksville 17 13 Carey 12 21
Danville 25 5 Whistler 11 19
Athens 27 7 Woodville 22 6
a. If we want to estimate crimes on the basis of the number of police, which variable is the dependent variable and which is the independent variable?
b. Draw a scatter diagram
c. Determine the coefficient of correltion
d. Determine the coefficient of determination
e. Interpret these statistical measures. Does it surprise you that the relationship is inverse?