69 True/False questions

The pvalue is less than or equal to alpha. → When the pvalue is used for hypothesis testing, the null hypothesis is rejected if...

6.38 → Forty percent of the students who enroll in a statistics course go to the statistics laboratory on a regular basis. Past data indicates that 80% of those students who use the lab on a regular basis make a grade of A in the course. If you randomly select one student from the class, what is the probability that this student went to the lab and received a grade of A? Enter your answer rounded to three decimal places.

Crosssectional Data → On a street, the houses are numbered from 300 to 450. The house numbers are examples of...

Decreases → For a given level of Type I error, as the sample size increases, the level of Type II error...

300 → The numbers of hours worked (per week) by 400 statistics students are shown below.
Number of hours Frequency
0  9 20
10  19 80
20  29 200
30  39 100
The cumulative frequency for the class of 20  29 is... 
Longer tail to the right than to the left → A histogram is said to be skewed to the right if it has a

Standard error of the mean decreases → As the sample size increases, the..

Ordinal Scale → After using a website you are ask to rate your experience. You are given the options of excellent, very good, good, and poor. This is an example of the

0.264 → The time required to load a truck is exponentially distributed with a mean of 30 minutes. What is the probability that a truck will take at least 40 minutes to load. Enter your answer as a decimal rounded to 3 decimal places...

0.25 → The assembly time for a product is uniformly distributed between 6 to 10 minutes.
The probability of assembling the product in 7 minutes or less is... 
The null hypothesis is true → When the smallest and largest percentage of items are removed from a data set and the mean is computed, the mean of the remaining data is...

6,573,92 → Playbill Magazine reported that the mean annual household income of its readers is $119,155. Assume this estimate of the mean is based on a sample of 80 households, and based on past studies, the population standard deviation is known to be $30,000. What is the margin of error at a 95% level of confidence? Round your answer to two decimal places and enter it without a dollar sign.

59 → In order to determine an interval estimate for the mean of a population with an unknown standard deviation, a sample of 60 items is selected. The mean of the sample is determined to be 23. What is the number of degrees of freedom for determining the appropriate tvalue?

Categorical Data → For a sample of coffee shop customers, the wait times in seconds were recorded. Wait time is an example of a variable that uses the...

Delinquency and mortgage type (prime & subprime) are dependent. → A survey collects information on mortgage delinquencies and foreclosures. In the most recent survey, 6% of all mortgages (prime & subprime) were delinquent. It was further found that 16% of subprime mortgages are delinquent. Thus, it can be concluded that...

12.5 → The sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to increase sales. To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 64 days of sales was selected. It was found that the average was $8,150 per day with a sample standard deviation of $1,200.

The population proportion is greater than .75 → In the past, 75% of the tourists who visited Chattanooga went to see Rock City. The management of Rock City recently undertook an extensive promotional campaign. They are interested in determining whether the promotional campaign actually increased the proportion of tourists visiting Rock City. The alternative hypothesis is...

0.05 → A population of 10,000 students spends an average of $12.50 a day on dinner. The standard deviation of the expenditure is $4. A simple random sample of 64 students is taken. what is the standard deviation of the sampling distribution of the sample mean? Round your answer to 3 decimal places and no dollar sign.

1. Systematic Sampling
2. Stratified Random Sampling
3. Cluster Sampling
4. Simple Random Sample → A standard normal distribution has a mean of [x] and a standard deviation of [y]. (This question expects numeric answers.) 
0.5 → A population of 10,000 students spends an average of $12.50 a day on dinner. The standard deviation of the expenditure is $4. A simple random sample of 64 students is taken. what is the standard deviation of the sampling distribution of the sample mean? Round your answer to 3 decimal places and no dollar sign.

Exponential probability distribution → A continuous probability distribution that is useful in describing the time, or space, between occurrences of an event is a(n)

Interval Scale → In the 2010 Census respondants are asked to select their sex as male or female. In this context sex is an example of the

Sidebyside bar chart → On a street, the houses are numbered from 300 to 450. The house numbers are examples of...

Report the average of the two results → Suppose an automobile manufacturer has created a new vehicle and wants the vehicle's city mpg to be at least 25 mpg. The manufacturer hires two organizations to test the new vehicle. The first organization obtains a sample average of 23 mph. The second obtains 28 mpg. Which of the following actions would be the most ethical?

0.174 → The average number of cars that pass through a rural intersection in a fifteen minute interval is 5.3. It can be assumed that the probability of an occurrence is the same in any twotime periods of equal length.
Determine the probability that there are 6 occurrences or less in fifteen minutes. Enter your answer as a decimal rounded to three places. 
0.683 → The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 20 pounds.
What percent of players weigh between 180 and 220 pounds? Round your answer to three decimal places. 
191.76 → A sample of 225 elements from a population with a standard deviation of 90 is selected. The sample mean is 180 and the margin of error at a 95% confidence level is 11.76. What is the upper value for a 95% confidence interval for the population mean?

0 → Michael's ComputeAll, a national computer retailer, has kept a record of the number of laptop computers they have sold for a period of 80 days. Their sales records are shown below:
Number of Laptops Sold Number of Days
0  19 5
20  39 15
40  59 30
60  79 20
80  99 10
The number of days in which the company sold less than 40 laptops is... 
A population parameter → For a sample of coffee shop customers, the wait times in seconds were recorded. Wait time is an example of a variable that uses the...

The number of elements in a data set → In a frequency distribution table, the sum of frequencies for all classes for a variable will always equal..

110 → The sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to increase sales. To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 64 days of sales was selected. It was found that the average was $8,150 per day with a sample standard deviation of $1,200.

Decreases → As the sample size increases, the margin of error..

1.984 → For a sample size of 75 determine the crtitical value for a twotail hypothesis test at a 5% level of significance when the population standard deviation is unknown. Round your answer to three decimal places.

Positive → A portion of the population selected to represent the population is called

20 → Michael's ComputeAll, a national computer retailer, has kept a record of the number of laptop computers they have sold for a period of 80 days. Their sales records are shown below:
Number of Laptops Sold Number of Days
0  19 5
20  39 15
40  59 30
60  79 20
80  99 10
The number of days in which the company sold less than 40 laptops is... 
A discrete random variable → For a sample of coffee shop customers, the wait times in seconds were recorded. Wait time is an example of a variable that uses the...

The posterior probabilities → Bayes' theorem is used to compute...

Observations → For a given level of Type I error, as the sample size increases, the level of Type II error...

0.841 → A population of 10,000 students spends an average of $12.50 a day on dinner. The standard deviation of the expenditure is $4. A simple random sample of 64 students is taken. what is the probability that these 64 students will spend less than $832? Enter your answer as a decimal and not as a percent and round your answer to 3 decimal places.

Must always be equal to 0 → After using a website you are ask to rate your experience. You are given the options of excellent, very good, good, and poor. This is an example of the

2.25 → The probability distribution for the number of goals the Lions soccer team makes per game is given below.
Number Of Goals Probability
0 0.05
1 0.25
2 0.25
3 0.30
4 0.15
The expected number of goals per game is 
Crosstabulation → The set of measurements collected for a particular element is (are) called...

0.315 → The student body of a large university consists of 60% female students. A random sample of 8 students is selected.
What is the probability that more than five of the students in the sample are female? Enter your answer as a decimal round to three places. 
Ratio Scale → For a sample of coffee shop customers, the wait times in seconds were recorded. Wait time is an example of a variable that uses the...

Range → The measure of location which is the most likely to be influenced by extreme values in the data set is the...

0.32 → Forty percent of the students who enroll in a statistics course go to the statistics laboratory on a regular basis. Past data indicates that 80% of those students who use the lab on a regular basis make a grade of A in the course. If you randomly select one student from the class, what is the probability that this student went to the lab and received a grade of A? Enter your answer rounded to three decimal places.

0.05 → The assembly time for a product is uniformly distributed between 6 to 10 minutes.
The probability of assembling the product in 7 minutes or less is... 
Sample → A portion of the population selected to represent the population is called

The interquartile range is... → Bayes' theorem is used to compute...

495 → A committee of 8 is to be selected from a group of 12 people. How many possible different committees can be selected?

Observational → For a sample of retired NFL players, data are collected on the number of concussions each experienced during his career. This study would be considered...

1.0 → The sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to increase sales. To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 64 days of sales was selected. It was found that the average was $8,150 per day with a sample standard deviation of $1,200.

0.717 → The student body of a large university consists of 60% female students. A random sample of 8 students is selected.
What is the probability that no more than three of the students in the sample are female? Enter your answer as a decimal round to three places. 
Nominal Scale → After using a website you are ask to rate your experience. You are given the options of excellent, very good, good, and poor. This is an example of the

0.069 → The time required to load a truck is exponentially distributed with a mean of 30 minutes. What is the probability that a truck will take at least 40 minutes to load. Enter your answer as a decimal rounded to 3 decimal places...

0.738 → "DRUGS R US" is a large manufacturer of various kinds of liquid vitamins. The quality control department has noted that the bottles of vitamins marked 6 ounces have an average of 6 ounces but vary in content with a standard deviation of 0.3 ounces. Assume the contents of the bottles are normally distributed. Ninety percent of the bottles will contain no more than how many ounces? Round your answer to 2 decimal places.

The size of the confidence interval to decrease → If we change a 99% confidence interval estimate to a 95% confidence interval estimate, we can expect...

4.8 → The student body of a large university consists of 60% female students. A random sample of 8 students is selected.
What is the expected number of females in the sample? 
0.2 → An experiment consists of four outcomes with P(E1) = 0.2, P(E2) = 0.2, and P(E3) = 0.4. The probability of outcome E4 is...

Narrower and more peaked → After using a website you are ask to rate your experience. You are given the options of excellent, very good, good, and poor. This is an example of the

1.993 → Determine the t value for a 95% confidence interval estimate for a sample size of 100. Round your answer to three decimal places.

Mean → The measure of location which is the most likely to be influenced by extreme values in the data set is the...

The sample size divided by the population size is great than five percent. → In computing the standard error of the mean, the finite population correction factor is used when...

Population based upon information contained in the sample → In the past, 75% of the tourists who visited Chattanooga went to see Rock City. The management of Rock City recently undertook an extensive promotional campaign. They are interested in determining whether the promotional campaign actually increased the proportion of tourists visiting Rock City. The alternative hypothesis is...

Sample Statistic → A portion of the population selected to represent the population is called

0.977 → The average number of cars that pass through a rural intersection in a fifteen minute interval is 5.3. It can be assumed that the probability of an occurrence is the same in any twotime periods of equal length.
Determine the probability that there are 6 occurrences or less in fifteen minutes. Enter your answer as a decimal rounded to three places. 
The trimmed mean → When the smallest and largest percentage of items are removed from a data set and the mean is computed, the mean of the remaining data is...

Type II → The measure of location which is the most likely to be influenced by extreme values in the data set is the...

Specified Answer for x: 0
Specified Answer for y: 1 → A standard normal distribution has a mean of [x] and a standard deviation of [y]. (This question expects numeric answers.)