Statistics unit 3
Use the following information for the next 3 questions. If the true proportion of people who support a political candidate is p=0.52 and if n=2000 people are surveyed, we want to determine the probability that the results of the survey will suggest the candidate is losing the election (getting less than 50% of the votes). What is the standard deviation of p^? (Round to 3 decimal places.)
0.011
Give the standard deviation of the sample distribution of p^. Give your answers in decimal form and round to three decimal places. (Example: 0.398)
0.018
What is the probability the survey results will show the candidate is losing even though the true p=0.52? (Round to 3 decimal places.)
0.037
What is the standard deviation of p^? (Round to three decimal places.)
0.046
Out of a random sample of 2,000 people in the United States, 168 reported making more than $75,000 a year. Calculate the sample proportion p^ of people in the United States who earn more than $75,000 each year. Give your answer accurate to three decimal places in decimal form. (Example: 0.398)
0.084
What is the probability that more than 45% of those in a survey would have received a phishing email? Give your answer in decimal form, rounding to three decimal places. (Example: 0.398)
0.127
Input the upper bound. (Round to three decimal places.)
0.86
What is the z-score? (Round to three decimal places.)
1.091
To conduct a hypothesis test for one proportion, two requirements must be met. Suppose p = 1/10. What is the smallest n can be and both requirements still be met?
100
If p=4/5, what is the smallest value of n that satisfies the requirements for a normally distributed p^?
50
Three brands of batteries are under study. It is suspected the lives of the three brands are different. An experiment is conducted to test the hypothesis. Five randomly selected batteries of each brand are selected. The time (in hours) until the battery is effectively dead (i.e. power output drops below a specified level) is measured for each battery. What type of analysis is best suited for this study? 1 sample z-test (sigma known) 2 independent sample t-test 2 paired sample t-test 1 sample t-test (sigma unknown) ANOVA
ANOVA
If you increase the sample size from 60 to 80, what do you expect to happen to the width of the confidence interval? Increase Decrease Stay the same
Decrease
What is the decision for this test? a=0.05 p=0.011 Fail to reject the null hypothesis. Reject the null hypothesis.
Reject the null hypothesis
The symbol for the true population proportion is which of the following? p p~ p^
p
Use the following information to answer the next 7 questions. A random sample of BYU-Idaho students was surveyed and asked if they were in favor of retaining the penny as a form of currency in the United States. Out of the 116 women surveyed, 80 said that they were in favor of retaining the penny as a form of currency. Of the 137 men surveyed, 91 said that they were in favor of retaining the penny. For these questions, let group 1 represent women and group 2 represent men. Construct a 95% confidence interval of the difference in the proportions of women who are in favor of retaining the penny and men who are in favor of retaining the penny. Remember that for this exercise, women are assigned to group 1 and men are assigned to group 2. Input the values below rounded to three decimal places. (Example: 2.335). Input the lower bound.
-0.09
For the next 9 questions, we will review the PTC tasting study with differentdata. Out of 70 females in the sample, 52 can taste PTC. Out of 59 males in the sample, 42 can taste PTC.Please use the data presented here: Let p1 be the proportion of females in the population who can taste PTC and let p2 be the proportion of males in the population who can taste PTC. The research question for this study is given here, "Is the proportion of females who can taste PTC different from the proportion of males who can taste PTC?" Input the lower bound. (Round to three decimal places)
-0.123
What z-score would you use? (Round to 3 decimal places.)
-1.79
Use the following information for the next 6 questions. For the water quality study in the reading, about 60% of the macroinvertebrate water quality indicators have historically been associated with good health. The researchers suspect that water quality in the area has decreased. They conduct a hypothesis test using significance level α=0.05 with the following hypotheses: H0:p=0.6Ha:p<0.6They collect new data and this time n=80 and x=38 indicate good health. Find the test statistic. (Round to three decimals.)
-2.282
Use the following information to answer the next 8 questions. A study was conducted to determine the proportion of American teenagers between 13 and 17 who smoke. Previous surveys showed that 15% percent of all teenagers smoke. A Gallup survey interviewed a nationally representative sample of 785 teenagers aged 13 to 17. Seventy-one teenagers in the survey acknowledged having smoked at least once in the past week. Does the study provide adequate evidence to conclude that the percentage of teenagers who smoke is now different than 15%? Be sure to answer all the questions whether or not the requirements are actually met. Give the test statistic. (Round your answers to three decimal places, Example: 0.567)
-4.673
Use the following information to answer the next 8 questions. A study was conducted to determine the proportion of American teenagers between 13 and 17 who smoke. Previous surveys showed that 15% percent of all teenagers smoke. A Gallup survey interviewed a nationally representative sample of 785 teenagers aged 13 to 17. Seventy-one teenagers in the survey acknowledged having smoked at least once in the past week. Does the study provide adequate evidence to conclude that the percentage of teenagers who smoke is now different than 15%? Be sure to answer all the questions whether or not the requirements are actually met. Give the P-value. (Round your answers to three decimal places, Example: 0.567)
0
Use the following information for the next 6 questions. For the water quality study in the reading, about 60% of the macroinvertebrate water quality indicators have historically been associated with good health. The researchers suspect that water quality in the area has decreased. They conduct a hypothesis test using significance level α=0.05 with the following hypotheses: H0:p=0.6Ha:p<0.6They collect new data and this time n=80 and x=38 indicate good health. What is the P-value for this test? (Round to three decimals.)
0.011
For the next 9 questions, we will review the PTC tasting study with differentdata. Out of 70 females in the sample, 52 can taste PTC. Out of 59 males in the sample, 42 can taste PTC.Please use the data presented here: Let p1 be the proportion of females in the population who can taste PTC and let p2 be the proportion of males in the population who can taste PTC. The research question for this study is given here, "Is the proportion of females who can taste PTC different from the proportion of males who can taste PTC?" Create a 95% confidence interval for p1 minus p2 . Input your answers for the point estimate, lower bound and upper bound. What is the point estimate for this 95% confidence interval?
0.031
Use the following information to answer the next 8 questions. A study was conducted to determine the proportion of American teenagers between 13 and 17 who smoke. Previous surveys showed that 15% percent of all teenagers smoke. A Gallup survey interviewed a nationally representative sample of 785 teenagers aged 13 to 17. Seventy-one teenagers in the survey acknowledged having smoked at least once in the past week. Does the study provide adequate evidence to conclude that the percentage of teenagers who smoke is now different than 15%? Be sure to answer all the questions whether or not the requirements are actually met. Determine the appropriate 95% confidence interval for the true proportion of teenage smokers. Input the lower bound. (Round to three decimal places)
0.07
Use the following information to answer the next 8 questions. A study was conducted to determine the proportion of American teenagers between 13 and 17 who smoke. Previous surveys showed that 15% percent of all teenagers smoke. A Gallup survey interviewed a nationally representative sample of 785 teenagers aged 13 to 17. Seventy-one teenagers in the survey acknowledged having smoked at least once in the past week. Does the study provide adequate evidence to conclude that the percentage of teenagers who smoke is now different than 15%? Be sure to answer all the questions whether or not the requirements are actually met. You suspect that the true proportion of teens who smoke is different than 15%. Conduct a hypothesis test to test your theory. Use a level of significance of α=0.05. Calculate the point estimator p^, the test statistic, and the P-value for this test. Give the point estimator p̂. (Round your answers to three decimal places, Example: 0.567)
0.09
Researchers published a study in which they considered the incidence among the elderly of various mental health conditions such as dementia, bi-polar disorder, obsessive compulsive disorder, delirium, and Alzheimer's disease. In the U.S., 45% of adults over 65 suffer from one or more of the conditions considered in the study. Calculate the probability that fewer than 320 out of the n = 750 adults over 65 in the study suffer from one or more of the conditions under consideration. Give your answer accurate to three decimal places in decimal form. (Example: 0.398)
0.1
What is the standard deviation of p^? (Round answer to the tenth place.)
0.1
Use the following information to answer the next 8 questions. A study was conducted to determine the proportion of American teenagers between 13 and 17 who smoke. Previous surveys showed that 15% percent of all teenagers smoke. A Gallup survey interviewed a nationally representative sample of 785 teenagers aged 13 to 17. Seventy-one teenagers in the survey acknowledged having smoked at least once in the past week. Does the study provide adequate evidence to conclude that the percentage of teenagers who smoke is now different than 15%? Be sure to answer all the questions whether or not the requirements are actually met. Input the upper bound. (Round to three decimal places)
0.111
What is the probability Brittnie gets at least 35 hits in her next 100 at bats? (Round to 3 decimal places.)
0.138
Use the following information to answer the next 7 questions. A random sample of BYU-Idaho students was surveyed and asked if they were in favor of retaining the penny as a form of currency in the United States. Out of the 116 women surveyed, 80 said that they were in favor of retaining the penny as a form of currency. Of the 137 men surveyed, 91 said that they were in favor of retaining the penny. For these questions, let group 1 represent women and group 2 represent men. Construct a 95% confidence interval of the difference in the proportions of women who are in favor of retaining the penny and men who are in favor of retaining the penny. Remember that for this exercise, women are assigned to group 1 and men are assigned to group 2. Input the values below rounded to three decimal places. (Example: 2.335). Input the upper bound.
0.141
Suppose you're testing against Ha:p≠0.62 and you have calculated the test statistic to be z=1.334. The area to the right of z=1.334 (under the standard normal density curve) is 0.091. What is the P-value of your hypothesis test?
0.182
For the next 9 questions, we will review the PTC tasting study with differentdata. Out of 70 females in the sample, 52 can taste PTC. Out of 59 males in the sample, 42 can taste PTC.Please use the data presented here: Let p1 be the proportion of females in the population who can taste PTC and let p2 be the proportion of males in the population who can taste PTC. The research question for this study is given here, "Is the proportion of females who can taste PTC different from the proportion of males who can taste PTC?" Input the upper bound. (Round to three decimal places)
0.185
Use the following information to answer the next 4 questions. Brittnie's batting average is 0.300. We want to determine the probability she will get more than 35 hits in her next 100 at bats (n=100 and p=0.3). What is p̂? (Round to two decimal places.)
0.35
Use the following information to answer the next 2 questions. Suppose n=24 and p=0.4. What is the mean of p^? (Round answer to the tenth place.)
0.4
Use the following information to answer the next 4 questions. First Data Corp. records indicate that in 2005, 43% of adult email users received a phishing email. A phishing email replicates an authentic site for the purpose of stealing personal information such as account numbers and passwords. Suppose a random sample of 800 adults will be surveyed on whether they have received phishing emails to determine recent trends. Give the mean of the sample distribution of p^. Give your answers in decimal form and round to two decimal places. (Example: 0.39)
0.43
Use the following information to answer the next 7 questions. A random sample of BYU-Idaho students was surveyed and asked if they were in favor of retaining the penny as a form of currency in the United States. Out of the 116 women surveyed, 80 said that they were in favor of retaining the penny as a form of currency. Of the 137 men surveyed, 91 said that they were in favor of retaining the penny. For these questions, let group 1 represent women and group 2 represent men. Compute the test statistic and the P-value for this test. Input the test statistic. (Round to two decimal places, Example: 1.23)
0.43
Use the following information for the next 6 questions. For the water quality study in the reading, about 60% of the macroinvertebrate water quality indicators have historically been associated with good health. The researchers suspect that water quality in the area has decreased. They conduct a hypothesis test using significance level α=0.05 with the following hypotheses: H0:p=0.6Ha:p<0.6They collect new data and this time n=80 and x=38 indicate good health. What is p^? (Round to three decimals.)
0.475
Create a 95% confidence interval for the true proportion of first degree murder trials in this state where the verdict is "guilty". Input the lower bound. (Round to three decimal places.)
0.64
Use the following information to answer the next 7 questions. A random sample of BYU-Idaho students was surveyed and asked if they were in favor of retaining the penny as a form of currency in the United States. Out of the 116 women surveyed, 80 said that they were in favor of retaining the penny as a form of currency. Of the 137 men surveyed, 91 said that they were in favor of retaining the penny. For these questions, let group 1 represent women and group 2 represent men. Input the P-value. (Round to three decimal places, Example: 0.234)
0.667
For the next 9 questions, we will review the PTC tasting study with differentdata. Out of 70 females in the sample, 52 can taste PTC. Out of 59 males in the sample, 42 can taste PTC.Please use the data presented here: Let p1 be the proportion of females in the population who can taste PTC and let p2 be the proportion of males in the population who can taste PTC. The research question for this study is given here, "Is the proportion of females who can taste PTC different from the proportion of males who can taste PTC?" Use the data in the table to find p̂2. (Round to three decimal places)
0.712
According to the last census (2010), the mean number of people per household in the United States is μ=2.58 (https://www.census.gov/prod/cen2010/briefs/c2010br-14.pdf (Links to an external site.)Links to an external site.). Assume a standard deviation of σ=0.75. You plan to take a random sample of 110 households, what is the probability the sample mean household size is between 2.5 and 2.66 people? (round your probabilities to three decimal places)
0.737
For the next 9 questions, we will review the PTC tasting study with differentdata. Out of 70 females in the sample, 52 can taste PTC. Out of 59 males in the sample, 42 can taste PTC.Please use the data presented here: Let p1 be the proportion of females in the population who can taste PTC and let p2 be the proportion of males in the population who can taste PTC. The research question for this study is given here, "Is the proportion of females who can taste PTC different from the proportion of males who can taste PTC?" Use the data in the table to find p1^. (Round to three decimal places)
0.743
Use the following information for the next four questions. A study of first degree murder trials was conducted in another state. A random sample of 60 people on trial for first degree murder was taken. Of these, 45 of the defendants were found guilty. Find p^, the point estimate of the proportion of first degree murder defendants who are found guilty in this state. (Round to three decimals.)
0.75
For the next two questions, determine the probability that more than 45% of those in a survey would have received a phishing email. What is the z-score for a 45% probability? (Round to three decimal places, Example: 3.456) Note: You should use your unrounded answer from the previous question in the calculation.
1.143
Suppose you had been in charge of designing the study. What sample size would be needed to construct a margin of error of 2% with 95% confidence? Use the prior point estimate of p* = 0.15 for this calculation. Round up to the nearest whole number. (For example, 144.1 would round to 145)
1225
To conduct a hypothesis test for one proportion, two requirements must be met. Suppose p = 1/2. What is the smallest n can be and both requirements still be met?
20
A survey of doctors is planned to see what percentage prescribe a certain medication. Find the sample size required to achieve a 2% margin of error if the confidence level is 95%. Assume there are no prior estimates for p. Round up to the nearest whole number. (For example, 144.1 would round to 145)
2401
If p=1/4, what is the smallest n that satisfies the requirement?
40
The political scientist conducts her survey and calculates p^=0.512. Which of the following is the most correct interpretation of this statistic? There is a 51.2% chance that a randomly selected registered voter in Maracopa County, AZ is a Democrat. 51.2% of all the registered voters in Maricopa County, AZ are Republicans. 51.2% of all the registered voters in Maricopa County, AZ are Democrats. 51.2% of the registered voters in the sample are Democrats.
51.2% of the registered voters in the sample are Democrats.
Suppose you are scientist and you want to use a confidence interval to estimate the true mean number of times a person in your city blinks each day. If the number of times a person blinks each day is normally distributed, how many measurements must you have in order to be sure the sampling distribution of x¯ is normal? n≥30 n≥10 np^≥10 and n(1−p^)≥10 np≥10 and n(1−p)≥10 np≥5 and n(1−p)≥5 Any n will do.
Any n will do.
What is the difference between a bar chart and a histogram? Each column of a bar chart represents a group defined by a categorical variable. Each column of a histogram represents a group defined by a quantitative variable. Each column of a bar chart represents a group defined by a quantitative variable. Each column of a histogram represents a group defined by a categorical variable. Bar charts and histograms are the same.
Each column of a bar chart represents a group defined by a categorical variable. Each column of a histogram represents a group defined by a quantitative variable.
In a pie chart, why are the slices (sectors) different sizes? The size of each slice is random. The size of each slice is determined by the number of categories. Each slice represents a category and the area of each slice represents the proportion of the total occupied by the category. Pie charts are more visually appealing when the slices are different sizes.
Each slice represents a category and the area of each slice represents the proportion of the total occupied by the category.
With α=0.05, what decision do you make? Fail to reject H0 Reject Ha Fail to reject Ha Reject H0
Fail to reject H0
Use the following information to answer the next 7 questions. A random sample of BYU-Idaho students was surveyed and asked if they were in favor of retaining the penny as a form of currency in the United States. Out of the 116 women surveyed, 80 said that they were in favor of retaining the penny as a form of currency. Of the 137 men surveyed, 91 said that they were in favor of retaining the penny. For these questions, let group 1 represent women and group 2 represent men. Based on the decision rule, what do you conclude? Fail to reject the null. There is sufficient evidence to suggest that there is a difference between the proportions of men and women who favor retaining the penny. Fail to reject the null. There is insufficient evidence to suggest that there is a difference between the proportions of men and women who favor retaining the penny. Reject the null. There is sufficient evidence to suggest that there is a difference between the proportions of men and women who favor retaining the penny. Reject the null. There is insufficient evidence to suggest that there is a difference between the proportions of men and women who favor retaining the penny.
Fail to reject the null. There is insufficient evidence to suggest that there is a difference between the proportions of men and women who favor retaining the penny.
For the next 2 questions suppose n=100, p=0.25, and p^=0.09. The requirements for constructing a confidence interval are satisfied. True False
False
For the next 9 questions, we will review the PTC tasting study with differentdata. Out of 70 females in the sample, 52 can taste PTC. Out of 59 males in the sample, 42 can taste PTC.Please use the data presented here: Let p1 be the proportion of females in the population who can taste PTC and let p2 be the proportion of males in the population who can taste PTC. The research question for this study is given here, "Is the proportion of females who can taste PTC different from the proportion of males who can taste PTC?" Which set of hypotheses is appropriate for addressing the research question? H0:p1=p2 Ha:p1≠p2 H0:p1=p2 Ha:p1<p2 H0:p1=p2 Ha:p1>p2 H0:p1=p2 Ha:p1^≠p2^
H0:p1=p2 Ha:p1≠p2
For the next 8 questions, we will review the "Mortality Rates and Day of Admission: Heart Attacks" study with different data. Out of 118519 who had a heart attack during a weekday 16713 had died. Out of 42447 that had a heart attack on the weekend, 6155 had died. Please use the data presented here: Let p1 be the proportion of patients who had a heart attack and were admitted on a weekday who died and let be the proportion patients who had a heart attack and were admitted on a weekend who died. The research question for this study is given here, "Is the proportion of patients who have a heart attack and are admitted to the hospital on a weekday who die less than the proportion of patients who have a heart attack and are admitted to the hospital on the weekend who die?" Use a significance level of α=0.05. Which set of hypotheses is appropriate for addressing the research question? H0:p1=p2Ha:p1<p2 H0:p1=p2Ha:p1≠p2
H0:p1=p2Ha:p1<p2
Use the following information to answer the next 7 questions. A random sample of BYU-Idaho students was surveyed and asked if they were in favor of retaining the penny as a form of currency in the United States. Out of the 116 women surveyed, 80 said that they were in favor of retaining the penny as a form of currency. Of the 137 men surveyed, 91 said that they were in favor of retaining the penny. For these questions, let group 1 represent women and group 2 represent men. You also want to perform a hypothesis test to see if there is a difference between the proportion of women who want to keep the penny and the proportion of men who want to keep the penny. Use a level of significance of α=0.05. Choose the correct alternative hypothesis. Ha: p1>p2 Ha: p1<p2 Ha: p1≠p2
Ha: p1≠p2
As part of his semester project, a BYU-Idaho Introductory Statistics student calculates a 95% confidence interval for the true percentage of BYU-Idaho students who are from Latin America. What does the phrase "95% confidence" mean? There's a 95% chance that the true proportion is in the confidence interval. 95% of the student's data are within the confidence intervals. If we create many 95% confidence intervals, 95% of them will contain the true proportion. The sample proportion is in 95% of the confidence intervals we make.
If we create many 95% confidence intervals, 95% of them will contain the true proportion.
Use the following information to answer the next 2 questions. A political scientist takes a simple random sample of n = 140 registered voters in Maricopa County, AZ to determine the proportion of registered voters who consider themselves Democrats. Assume the (unknown) true proportion of registered voters who are Democrats is 46%. Calculate the mean and standard deviation of the distribution of sample proportions for this study. Mean = 0.46, Standard deviation = 0.042 Mean = 0.46, Standard deviation = 0.573 Mean = 0.042, Standard deviation = 0.46 Mean = 0.573, Standard deviation = 0.46
Mean = 0.46, Standard deviation = 0.042
A study is planned to compare the proportion of men who dislike anchovies with the proportion of women who dislike anchovies. The study seeks to determine if the proportions of men and women who dislike anchovies are different. A sample of 41 men was taken and the p^ estimate for the true proportion of men who dislike anchovies was determined to be 0.66. A sample of 56 women was also taken and the p^ estimate for the true proportion of women who dislike anchovies was determined to be 0.84. Are the requirements satisfied to perform this hypothesis test? Why? Yes, because the sample sizes of both groups are greater than 5. Yes, because in both cases np^≥10 Yes, because we know that the populations are normally distributed. No, because in at least one case n(1−p^)<10
No, because in at least one case n(1−p^)<10
Your little brother has a career batting average of 0.233. You want to determine the probability that he will have a batting average of over 0.250 next season when he will be up to bat 40 times. Are the conditions met so that the sample proportion p^ will be approximately normal? Yes. There is a large sample, n>30, so the conditions are satisfied. No. p^ can only be normal if the sample data are normally distributed. Yes. 40×0.25≥10 so the conditions are satisfied. No. 40×0.233<10 so the conditions are not satisfied.
No. 40×0.233<10 so the conditions are not satisfied.
A credit card company estimates that the average credit card balance of Americans is $3,210. A statistics student wants to know whether this is true for citizens of her home town. Which hypothesis test would be most appropriate for addressing this question? One mean (sigma known) One mean (sigma unknown) Mean of the differences (paired samples) Difference of two means (independent samples) ANOVA (several means) One proportion Two proportions
One mean (sigma unknown)
Many ground level plants in tropical rainforests have adapted to the shade of the forest canopy. These plants tend to function well as house plants since they require minimal sunlight. A botanist is interested in "domesticating" a particular plant found in the Amazon rainforest. The botanist wants to estimate the true proportion of this species of plant that will survive inside. Assuming an appropriate sample can be obtained, which confidence interval would be most appropriate for this task? One mean (sigma known) One mean (sigma unknown) Mean of the differences (paired samples) Difference of two means (independent samples) One proportion Difference of two proportions
One proportion
Different counties across the US have different property tax rates for residential properties. A financial economist wants to estimate the true mean US tax rate for residential properties. Which confidence interval would be most appropriate in this situation? One sample confidence interval for the mean using z (sigma known) One sample confidence interval for the mean using t (sigma unknown) Paired-samples t-confidence interval Independent samples t-confidence interval Confidence interval for one proportion
One sample confidence interval for the mean using t (sigma unknown)
Use the following information to answer the next 8 questions. A study was conducted to determine the proportion of American teenagers between 13 and 17 who smoke. Previous surveys showed that 15% percent of all teenagers smoke. A Gallup survey interviewed a nationally representative sample of 785 teenagers aged 13 to 17. Seventy-one teenagers in the survey acknowledged having smoked at least once in the past week. Does the study provide adequate evidence to conclude that the percentage of teenagers who smoke is now different than 15%? Be sure to answer all the questions whether or not the requirements are actually met. (p value= 0 and alpha = 0.05) Based on the decision rule, what do you conclude? Fail to reject the null. There is sufficient evidence to suggest that the true proportion of teenagers who smoke is different than 15% . Fail to reject the null. There is insufficient evidence to suggest that the true proportion of teenagers who smoke is different than 15% . Reject the null. There is sufficient evidence to suggest that the true proportion of teenagers who smoke is different than 15% . Reject the null. There is insufficient evidence to suggest that the true proportion of teenagers who smoke is different than 15% .
Reject the null. There is sufficient evidence to suggest that the true proportion of teenagers who smoke is different than 15% .
A marriage counselor conducted a study of couples, categorizing each of the couples as "communicative" or "non-communicative". Among other things, the counselor wanted to see whether the percentage of communicative couples whose marriage ended in separation or divorce was the same as the percentage of non-communicative couples whose marriage ended in separation or divorce. Which hypothesis test would be most appropriate for this study? One sample z-test One sample t-test Paired-samples t-test Independent samples t-test ANOVA Test of one proportion Test of two proportions
Test of two proportions
How are Bar charts and Pareto charts related? Pareto charts are constructed from tossing a coin several times. They are identical. The only difference between a Bar chart and a Pareto chart is that the bars in a Pareto chart are ordered largest to smallest going from left to right.
The only difference between a Bar chart and a Pareto chart is that the bars in a Pareto chart are ordered largest to smallest going from left to right.
What is n? The number of successes. The number of candidates in an election. The sample size.
The sample size.
Which of the following statements best describes the outcome of this study. There is insufficient evidence to suggest that the true proportion of females who can taste PTC is less than the true proportion of males who can taste PTC. There is sufficient evidence to suggest that the true proportion of females who can taste PTC is greater than the true proportion of males who can taste PTC. There is sufficient evidence to suggest that the true proportion of females who can taste PTC is different from the true proportion of males who can taste PTC. There is insufficient evidence to suggest that the true proportion of females who can taste PTC is different from the true proportion of males who can taste PTC.
There is insufficient evidence to suggest that the true proportion of females who can taste PTC is different from the true proportion of males who can taste PTC.
Use the following information for the next 6 questions. For the water quality study in the reading, about 60% of the macroinvertebrate water quality indicators have historically been associated with good health. The researchers suspect that water quality in the area has decreased. They conduct a hypothesis test using significance level α=0.05 with the following hypotheses: H0:p=0.6Ha:p<0.6They collect new data and this time n=80 and x=38 indicate good health. (Rejected the null hypothesis) Which of the following best summarizes the conclusion of this test? There is sufficient evidence to conclude that water quality in the area has not decreased. There is insufficient evidence to conclude that water quality in the area has not decreased. There is insufficient evidence to conclude that water quality in the area has decreased. There is sufficient evidence to conclude that water quality in the area has decreased.
There is sufficient evidence to conclude that water quality in the area has decreased.
For the next 8 questions, we will review the "Mortality Rates and Day of Admission: Heart Attacks" study with different data. Out of 118519 who had a heart attack during a weekday 16713 had died. Out of 42447 that had a heart attack on the weekend, 6155 had died. Please use the data presented here: Let p1 be the proportion of patients who had a heart attack and were admitted on a weekday who died and let be the proportion patients who had a heart attack and were admitted on a weekend who died. The research question for this study is given here, "Is the proportion of patients who have a heart attack and are admitted to the hospital on a weekday who die less than the proportion of patients who have a heart attack and are admitted to the hospital on the weekend who die?" Use a significance level of α=0.05. The conditions for conducting a hypothesis test are satisfied. True False
True
The requirements for conducting a hypothesis test are satisfied. True False
True
Use the following information for the next 3 questions. We conclude that p^ is normally distributed if np≥10 and n(1−p)≥10. Is p the true proportion or the sample proportion? Sample proportion True proportion
True proportion
Use the following information to answer the next 8 questions. A study was conducted to determine the proportion of American teenagers between 13 and 17 who smoke. Previous surveys showed that 15% percent of all teenagers smoke. A Gallup survey interviewed a nationally representative sample of 785 teenagers aged 13 to 17. Seventy-one teenagers in the survey acknowledged having smoked at least once in the past week. Does the study provide adequate evidence to conclude that the percentage of teenagers who smoke is now different than 15%? Be sure to answer all the questions whether or not the requirements are actually met. Are the requirements for both a confidence interval and a hypothesis test met? Yes, np≥10 and n(1−p)≥10, np^≥10 and n(1−p^)≥10 so the requirements are met. Yes. There is a large sample n>30 so the requirements are met. No. p^<10 so the requirements for a hypothesis test are not met. No. The requirements for a confidence interval can only be met if the sample data are normally distributed.
Yes, np≥10 and n(1−p)≥10, np^≥10 and n(1−p^)≥10 so the requirements are met.
Are the requirements for conducting a χ2 test for independence met by this data set? Yes, there are at least 5 expected counts in each cell. No, there are too many columns in the table. Yes, all of the expected cell counts are greater than 30. Yes, there are 5 observed counts in at least one cell. No, there aren't enough rows in the table.
Yes, there are at least 5 expected counts in each cell.
Use the following information to answer the next 7 questions. A random sample of BYU-Idaho students was surveyed and asked if they were in favor of retaining the penny as a form of currency in the United States. Out of the 116 women surveyed, 80 said that they were in favor of retaining the penny as a form of currency. Of the 137 men surveyed, 91 said that they were in favor of retaining the penny. For these questions, let group 1 represent women and group 2 represent men. Are the requirements met to create a confidence interval and conduct a hypothesis test? Yes. The requirements are met for both. No. The requirements aren't met for a confidence interval or a hypothesis test. The requirements are only met for creating a confidence interval. The requirements are only met for conducting a hypothesis test.
Yes. The requirements are met for both.
What is the equation for computing the degrees of freedom (df) for this hypothesis test in chi square test? df=(number of rows +1)⋅(number of columns+1) df=number of rows⋅number of columns df=(number of rows −1)⋅(number of columns−1) df=n−1
df=(number of rows −1)⋅(number of columns−1)
Use the following information for the next 6 questions. For the water quality study in the reading, about 60% of the macroinvertebrate water quality indicators have historically been associated with good health. The researchers suspect that water quality in the area has decreased. They conduct a hypothesis test using significance level α=0.05 with the following hypotheses: H0:p=0.6Ha:p<0.6They collect new data and this time n=80 and x=38 indicate good health. The conditions for conducting a hypothesis test are satisfied. true false
true
