Question

The results below are based on data collected as part of a student project for an introductory statistics class at UF. If there is more than one group/treatment, the first group mentioned is group 1. Data was collected to determine if the price of food items at Graham Oasis (a convenience store inside UF campus) is higher, on average, than at a Publix Supermarket located 2 miles away. The p-value was 0.000, and the confidence interval was ( 0.85, 1.62).

The students selected food items and checked their prices at both stores.

This problem is about [ Select ]["two independent proportions", "dependent means", "two independent means", "one mean", "one proportion", "dependent proportions"] .

The sign of the alternative hypothesis should be [ Select ] [">", "=", "not =", "<"] .

Based on the p-value we can [ Select ] ["Reject the Null Hypothesis", "not Reject the Alternative Hypothesis", "Reject the Alternative Hypothesis", "Accept the Null Hypothesis", "not Reject the Null Hypothesis", "Accept the Alternative Hypothesis"] at alpha = 0.05.

At which alpha levels could we Reject Ho? [ Select ] ["all of the usual alpha levels", "0.10 and 0.05", "0.01 and 0.05", "none of the usual alpha levels"]

Are the results statistically significant at alpha=0.01? [ Select ] ["Yes.", "No."] We have [ Select ] ["some evidence", "very strong evidence", "not enough evidence", "pretty strong evidence"] to say that the average price of food items at Graham Oasis is higher than Publix.

We are 95% confident that the average price of food items at Graham Oasis is between [ Select ] ["85 cents and $1.62 lower", "$1.62 lower and 85 cents higher", "85 cents lower and $1.62 higher", "85 cents and $1.62 higher"] than at Publix.

The results of the confidence interval and significance test at alpha=0.05 [ Select ] ["do not agree because the test is one sided.", "agree", "do not agree because the test is two sided."] .

The population of interest is [ Select ] ["all food items", "all food items available at at least one of the stores", "all food items available at both stores", "all items for which data was collected"] .

We need to assume the sample was randomly selected because we are making inferences about [ Select ] ["two groups", "one group", "an unknown parameter", "proportions", "an unknown statistic", "means", "an estimator"] .

For the students collecting the data, it would be [ Select ] ["very difficult", "fairly easy"] to select a random sample from this population.

Students collecting the data should strive for [ Select ] ["a sample size of at least 30", "at least 15 successes and 15 failures in the population", "a population size of at least 30", "at least 15 successes and 15 failures in the sample"]

Answer 1

This problem is about "two independent means".

The sign of the alternative hypothesis should be ">".

Based on the p-value we can "Reject the Null Hypothesis" at alpha = 0.05.

At which alpha levels could we Reject Ho? "all of the usual alpha levels".

Are the results statistically significant at alpha=0.01? "Yes." We have "very strong evidence" to say that the average price of food items at Graham Oasis is higher than Publix.

We are 95% confident that the average price of food items at Graham Oasis is between "85 cents and $1.62 higher" than at Publix.

The results of the confidence interval and significance test at alpha=0.05 "agree".

The population of interest is "all food items".

We need to assume the sample was randomly selected because we are making inferences about "two groups".

For the students collecting the data, it would be "fairly easy" to select a random sample from this population.

Students collecting the data should strive for "a sample size of at least 30".