Is the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years.† Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 33 arrests last month, 26 were of males aged 15 to 34 years. Use a 1% level of significance to test the claim that the population proportion of such arrests is the city different from 70%. Solve the problem using both the traditional method and the P-value method. Since the sampling distribution of p̂ is the
test statistic | = | |
critical value | = ± | |
P-value | = |
State your conclusion in the context of the application.
Compare your conclusion with the conclusion obtained by using the P-value method. Are they the same?
Trending nowThis is a popular solution!
Step by stepSolved in 5 steps with 9 images
- Is the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years†. Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 33 arrests last month, 19 were of males aged 15 to 34 years. Use a 1% level of significance to test the claim that the population proportion of such arrests in Rock Springs is different from 70%. (a) What is the level of significance?State the null and alternate hypotheses. H0: p = 0.7; H1: p > 0.7H0: p < 0 .7; H1: p = 0.7 H0: p = 0.7; H1: p ≠ 0.7H0: p ≠ 0.7; H1: p = 0.7H0: p = 0 .7; H1: p < 0.7 (b) What sampling distribution will you use? The Student's t, since np < 5 and nq < 5.The standard normal, since np < 5…arrow_forwardIs the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years†. Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 37 arrests last month, 24 were of males aged 15 to 34 years. Use a 5% level of significance to test the claim that the population proportion of such arrests in Rock Springs is different from 70%. What is the level of significance? ___ What is the value of the sample test statistic? (Round your answer to two decimal places.) ___ Find the P-value of the test statistic. (Round your answer to four decimal places.) _____arrow_forwardSuppose that you would like to determine if the use of the newest Sweeney education intervention will improve students understanding of statistics better than the use of no intervention. In order to do this, you select two groups of students at random from students who need to take Statistics: a group given the intervention and another group that is given the standard statistics class. At the end of the course, the students were given an exam and the exam scores were compared. Group 1: Students given the interventionGroup 2: Students in the standard Statistics class Use this information to answer the following questions:a. What test should you run and why?b. What is the null hypothesis? What is the alternative hypothesis?c. What requirements would have to be met to insure that you could run the test?arrow_forward
- Is the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years†. Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 34 arrests last month, 23 were of males aged 15 to 34 years. Use a 5% level of significance to test the claim that the population proportion of such arrests in Rock Springs is different from 70%. What is the level of significance? ____ What is the value of the sample test statistic? (Round your answer to two decimal places.) _____ Find the P-value of the test statistic. (Round your answer to four decimal places. ______arrow_forward3. A psychology professor wants to know if stress in his statistics class is in anyway affected by a student's major and gender. Test to see if a student's gender and major affects their stress level in the statistics course. Psychology Other 17 11 -1 12 9 12 17 9 Male 10 10 13 13 13 4 14 6 EX² = 1294 EX² 811 25 19 15 14 11 20 20 12 Female 3 20 12 15 18 10 20 25 EX² = 2248 ΣΧ' = 2451 Solve for the appropriate test statistic(s).arrow_forwardMatrimony Monthly is a top-selling magazine that provides information for couples thinking about marriage. Over the years, writers for the magazine have researched just about everything there is to research about weddings. The popular conception at the magazine has been that roughly 50% of first weddings take place indoors in a church, 30% take place indoors in a building other than a church, and 20% take place outdoors. This past week, the magazine examined a random sample of 280 first weddings and found the distribution given by the first row of numbers in the table below. (This row contains the frequencies observed in their sample of 280.) The second row of numbers gives the frequencies expected under the hypothesis that the popular conception at the magazine is correct. The bottom row of numbers contains the following value for each of the wedding location categories. −fOfE2 fE = −Observed frequencyExpected frequency2 Expected…arrow_forward
- The table below gives the number of suicides estimated in the U.S. for a recent year by age, race (black or white), and sex. We are interested in possible relationships between age, race, and sex. We will let suicide victims be our population. Race and Sex 1-14 15-24 25-64 over 64 TOTALS white, male 210 3,360 13,610 22,050 white, female 75 585 3,385 4,930 black, male 10 460 1,065 1,670 black, female 0 45 265 330 all others TOTALS 310 4,650 18,780 29,760arrow_forwardIs the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years†. Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 37 arrests last month, 25 were of males aged 15 to 34 years. Use a 10% level of significance to test the claim that the population proportion of such arrests in Rock Springs is different from 70%. -Find the P-value of the test statistic. (Round your answer to four decimal places.)ANSWER IS NOT 0.3745arrow_forwardIs the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years†. Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 37 arrests last month, 22 were of males aged 15 to 34 years. Use a 10% level of significance to test the claim that the population proportion of such arrests in Rock Springs is different from 70%.arrow_forward
- A warehouse manager wants to know if there is an association between the shift worked and being on time for work. To investigate, he selects a random sample of 70 workers and classifies each one according to the shift they worked most recently and whether they were on time for work. He was unable to classify a substantial number of people as being on time, so he classified those individuals as unknown. The data are displayed in the table. The manager would like to know if these data provide convincing evidence of an association between the shift worked and being on time in the large population of all workers at this warehouse. The random and 10% conditions are met. Is the Large Counts condition met? Yes, the smallest expected count is 5, so all expected counts are at least 5. Yes, the smallest expected count is 8.54, so all expected counts are at least 5. No, the smallest expected count is 2.56, so the expected counts are not all at least 5. No, the smallest expected count is…arrow_forwardA report describes a survey of 251 adult Americans. Participants in the survey were asked how often they disinfect their phone and were asked to respond with one of the following categories: more than once a week, once a week, every other, week, every three weeks, or less often than every three weeks. For this group, 9% responded more than once a week, 52% responded once a week, 26% responded every other week, 6% responded every three weeks, and 7% responded less often than every three weeks. Fill in the table below with the relative frequency distributions. How Often? Relative Frequency More than once a week Once a week Every other week Every three weeks Less often than every three weeksarrow_forwardIs the national crime rate really going down? Some sociologists say yes! They say that the reason for the decline in crime rates in the 1980s and 1990s is demographics. It seems that the population is aging, and older people commit fewer crimes. According to the FBI and the Justice Department, 70% of all arrests are of males aged 15 to 34 years†. Suppose you are a sociologist in Rock Springs, Wyoming, and a random sample of police files showed that of 37 arrests last month, 19 were of males aged 15 to 34 years. Use a 1% level of significance to test the claim that the population proportion of such arrests in Rock Springs is different from 70%. (a) What is the level of significance? 0.01 What is the value of the sample test statistic? (Round your answer to two decimal places.) ?? (c) Find the P-value of the test statistic. (Round your answer to four decimal places.)???arrow_forward
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman