In: Statistics and Probability
The Employment and Training Administration reported the U.S. mean unemployment insurance benefit was $238 per week (The World Almanac 2003). A researcher in the state of Virginia anticipated that sample data would show evidence that the mean weekly unemployment insurance benefit in Virginia was below the national level. a. Develop appropriate hypotheses such that rejection of H0 will support the researcher's contention.
b. For a sample of 120 individuals, the sample mean weekly unemployment insurance benefit was $231 with a sample standard deviation of $60. The p-value is:
c. Using level of signifigance = .05, can you conclude that the mean weekly unemployment insurance benefit in Virginia is below the national level?
d. Using level of signifigance = .05, what is the critical value for the test statistic (to 2 decimals)?
e. State the rejection rule: Reject H0 if t is - Select your answer -greater than or equal to ,greater than,less than or equal to,less than equal to not equal to Item 6 the critical value.
f. Using = .05, can you conclude that the mean weekly unemployment insurance benefit in Virginia is below the national level?
a)
Ho : µ = 238
Ha : µ < 238
b)
sample std dev , s =
60.0000
Sample Size , n = 120
Sample Mean, x̅ = 231.0000
degree of freedom= DF=n-1= 119
Standard Error , SE = s/√n = 60.0000 / √
120 = 5.4772
t-test statistic= (x̅ - µ )/SE = (
231.000 - 238 ) /
5.4772 = -1.28
p-Value = 0.1019 [Excel
formula =t.dist(t-stat,df) ]
c)
Level of Significance , α =
0.05
Decision: p-value>α, Do not reject null
hypothesis
Conclusion: There is not enough evidence to conclude that the mean
weekly unemployment insurance benefit in Virginia is below the
national level
d)
critical t value, t* = -1.6578 [Excel formula =t.inv(α/no. of tails,df) ]
e)
Reject H0 if t is greater than -1.28
f)
critical t value, t* = -1.6578 < -1.28
so
Do not reject null hypothesis
Conclusion: There is not enough evidence to conclude that
the mean weekly unemployment insurance benefit in Virginia is below
the national level