An ANOVA has three sources of variation. They are _____, _____, and _____.
We are interested in knowing if the following frequency distribution is normally
distributed. The population mean and standard deviation of the data are 600 and 160,
respectively.
If the distribution was normally distributed, what is the probability that an observation
would be a member of the “800 up to 1000” class?
A multiple regression analysis showed the following ANOVA table result.
Based on the information in the ANOVA, what is the decision regarding the global null
hypothesis?
The best model to describe a linear relationship between two variables is the
_______________________.
A local grocery store wants to estimate the mean daily number of gallons of milk sold
to customers. Assume the number of gallons sold follows the normal distribution, with a
population standard deviation of 5.10 gallons. A random sample of 60 days shows that
the mean daily number of gallons sold is 10.00. What is the point estimate of the
population mean?
When independent samples are used to test for differences in the population means with
equal but unknown population standard deviations, we _______ these sample standard
deviations.
A financial planner wants to compare the yield of income and growth mutual funds.
Fifty thousand dollars is invested in each of a sample of 35 income and 40 growth
funds. The mean increase for a two-year period for the income funds is $900. For the
growth funds, the mean increase is $875. Income funds have a sample standard
deviation of $35; growth funds have a sample standard deviation of $45. Assume that
the population standard deviations are equal.
At the 0.05 significance level, is there a difference in the mean yields of the two funds?
What is the computed value of the test statistic?
The t distribution approaches the ____________ distribution as the sample size
increases.
If an employee wanted to investigate the relationship between performance rating and
gender, what type of analysis should be used?
High school students were interested in a teacher’s claim that the longer the length of
time (hours) that a student studies for a test, the higher the test score. The students
collected the data and the teacher did the regression analysis with the following results.
To test the null hypothesis that the slope is zero, what are the t test statistic and the
t-critical values using the 0.05 significance level?
A local health care company wants to estimate the mean weekly elder day-care cost. A
sample of 10 facilities shows a mean of $250 per week, with a standard deviation of
$25. What is the 90% confidence interval for the population mean?
