--%>

Compare the test results

The grade point averages of 61 students who completed a college course in financial accounting have a standard deviation of .790. The grade point averages of 17 students who dropped out of the same course have a standard deviation of .940. Do the data indicate a difference between the variances of grade point averages for students who completed a financial accounting course and students who dropped out? Use α = .05 level of significance. Use both p-value and critical value approaches. Compare the test results.

 

E

Expert

Verified

Data

N1 = 61, SD1 = 0.79, N2 = 17, SD2 = 0.94

S12 = 0.792 = 0.6241

S22 = 0.942 = 0.8836

Hypothesis Formation

H0: σ1 = σ2

H1: σ1 ≠ σ 2

Test Stastistics

F =S12/S22

Critical Region

Reject H0 in favor of alternative if F test statistic lesser than the critical value of F critical value or lesser than -F critical value.

i.e F-test statistic > critical value of F OR F-test statistic < critical value of -F

Critical value of F at 0.05 Significance Level for two tail test

Df1 = N1 - 1 = 61 - 1 = 60

Df2 = N1 - 1 = 17 - 1 = 16

Critical value of F with df 8 and alpha 0.05 = F0.05/2,60,16 = 2.45

Computation

F-Statistic = 0.6241/0.8836

    = 0.71

Decision

As F statistic is neither greater than 2.45 nor smaller than -2.45 so we can not reject null hypothesis. P-value can't be determine in this manually however it can be said that it will be at least greater than the tolerance level of 0.05.

   Related Questions in Basic Statistics

  • Q : Derived quantities in Queuing system

    Derived quantities in Queuing system: • λ = A / T, Arrival rate • X = C / T, Throughput or completion rate • ρ =U= B / T, Utilization &bu

  • Q : Variance and standard error A hospital

    A hospital treated 412 skin cancer patients over a year. Of these, 197 were female. Give the point estimate of the proportion of females seeking treatment for skin cancer. Give estimates of the

  • Q : Safety and Liveness in Model Checking

    Safety and Liveness in Model Checking Approach; •? Safety: Nothing bad happens •? Liveness: Something good happens •? Model checking is especially good at verifying safety and liveness properties    –?Concurrency i

  • Q : Explain Service times Service times: A)

    Service times:A) In most cases, servicing a request takes a “short” time, but in a few occasions requests take much longer.B) The probability of completing a service request by time t, is independent of how much tim

  • Q : Cumulative Frequency and Relative

    Explain differences between Cumulative Frequency and Relative Frequency?

  • Q : Simplified demonstration of Littles Law

    Simplified demonstration of Little’s Law:

    Q : Define Operational Analysis

    Operational Analysis: • Analysis method based on the measurement of the operational characteristics of the system.

    Q : Sample z test and Sample t test A

    A random sample X1, X2, …, Xn is from a normal population with mean µ and variance σ2. If σ is unknown, give a 95% confidence interval of the population mean, and interpret it. Discuss the major diff

  • Q : Data Description 1. If the mean number

    1. If the mean number of hours of television watched by teenagers per week is 12 with a standard deviation of 2 hours, what proportion of teenagers watch 16 to 18 hours of TV a week? (Assume a normal distribution.) A. 2.1% B. 4.5% C. 0.3% D. 4.2% 2. The probability of an offender having a s

  • Q : Computers playing games How Computers

    How Computers playing games can be categorized according to different dimensions?