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You are interested in testing the difference between pre-incarceration and post-release average number of arrests for a sample of prisoners. You are assuming a normal distribution. You believe that post incarceration arrests will be lower than pre-sanction arrests. Test using alpha =0.05 Use the following Excel data Note: Only one table is the correct test t-Test: Two-Sample Assuming Equal Variances   Pre-sanction Post-release Mean 8.3 7.4 Variance 16.6777778 6.711111 Observations 10 10 Pooled Variance 11.6944444 Hypothesized Mean Difference 0 df 18 t Stat 0.58848814 P(T

You have decided to analyze a set of data with a 2 sample t-test for independent groups.  What thumb rule do you use to determine if you should assume equal or unequal variances?

Which hypothesis test should you perform for the following scenario? You survey a sample of 100 students from Partytime High School and 100 students from Funtime High School, and find that those from Partytime High school have smoked marijuana 2.1 times (s=0.6) in the last month, while those at Funtime High School have smoked marijuana an average of 1.5 times (s=0.5).  

When testing a single sample mean for significance when the population standard deviation is unknown and sample size is 75, the correct sampling distribution is  

The following is an example of a null hypothesis: The average time to recidivate for a male is less than the average time to recidivate for a female

The Central Limit Theorem states that as sample size becomes large

Which hypothesis test should you perform for the following scenario? You have reason to believe that high risk-seeking youths commit more delinquent acts than low risk-seeking youths. You known from reputable sources that the distribution of number of delinquent acts is approximately normal in the population for both types of youths. In order to answer your research question, you gather a SRS on 40 low risk-seeking youths and 40 high risk-seeking youths to find the mean level of delinquent acts for each group. Based on this information, you should use which test?

For the Central Limit Theorem — a. State the theorem b. Why is this theorem useful?

What do we call a hypothesis test when the alternative hypothesis includes a possible difference in either direction?

What is the primary purpose of a 95% confidence interval for a mean?