Statistics Final

Of the two production methods, a company wants to identify the method with the smaller population mean completion time. One sample of workers is selected and each worker first uses one method and then uses the other method. The sampling procedure being used to collect completion time data is based on

matched samples

A two-tailed test is performed at the .05 level of significance. The p-value is determined to be .01. The null hypothesis

must be rejected

When the null hypothesis is rejected, it is

possible a Type I error has occurred

The standard error of x1-x2 is the

standard deviation of the sampling distribution of x1-x2 .

Potential sampling error _____as the sample size increases.

decreases

What type of error occurs if you fail to reject H0 when, in fact, it is not true?

type 1

Read the z statistic from the normal distribution table and choose the correct answer. For a one-tailed test (upper tail) using α = .0721, z =

1.46

A sample of 100 information systems managers had an average hourly income of $40.00 with a standard deviation of $8.00. If we want to determine a 95% confidence interval for the average hourly income of the population, the value of t is

1.993

The use of the normal probability distribution as an approximation of the sampling distribution of is based on the condition that both np and n(1 - p) equal or exceed

5

The degrees of freedom associated with a t distribution are a function of the

Sample size

If a hypothesis test leads to the rejection of the null hypothesis, a _____ have been committed.

Type I error may

In hypothesis tests about a population proportion, p0 represents the

hypothesized population proportion

The value added to and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as the

margin of error

When developing an interval estimate for the difference between two population means with sample sizes of n1 and n2

n1 and n2 can be of different sizes

In hypothesis testing, if the null hypothesis has been rejected when the alternative hypothesis has been true,

the correct decision has been made.