Exam 25: Comparing Counts

Research is conducted regarding the average age at retirement for four career groups.To test whether there is a relationship between age of retirement and career in these groups,700 employees,recently retired,are randomly selected.The resulting data are displayed in the contingency table below. Does the data provide sufficient evidence to conclude that an association exists between age of retirement and career? Use a 5% level of significance.

The two-way table summarizes data from the human resource department at a university: New Hires What is the probability (rounded to three decimal places)that a female new hire is adjunct?

A publishing company performs sample surveys to obtain information on characteristics of book readers.A book reader is defined to be one who read one or more books in the six months prior to the survey;a non-book reader is defined to be one who read newspapers or magazines but no books in the six months prior to the survey;a nonreader is defined to be one who did not read a book,newspaper,or magazine in the six months prior to the survey.The following data were obtained in a random sample of 1429 persons 16 years old and over in an effort to determine whether or not the proportions of book readers,non-book readers,and non-readers are the same for each income bracket.Use a 1% level of significance. = 114.534;P-value = 2.287 ×

Tests for adverse reactions to a new drug yielded the results given in the table.Is the treatment (drug or placebo)independent of the reaction (whether or not headaches were experienced)? Use a 5% level of significance.

Test the claim that workplace accidents are distributed on workdays as follows: Monday 25%,Tuesday: 15%,Wednesday: 15%,Thursday: 15%,and Friday: 30%. In a study of 100 workplace accidents,24 occurred on a Monday,15 occurred on a Tuesday,17 occurred on a Wednesday,18 occurred on a Thursday,and 26 occurred on a Friday.Use a 10% level of significance.

Tests for adverse reactions to a new drug yielded the results given in the table.The data will be analyzed to determine if they provide sufficient evidence to conclude that an association exists between the treatment (drug or placebo)and the reaction (whether or not headaches were experienced).

A company manager wishes to test a union leader's claim that absences occur on the different week days with the same frequencies.He compiled the following data. Test statistic: χ² = 28.308 P-value = 0.0000108

A researcher performed a study to determine whether an association exists between sex and blood type.He obtained the following data from a random sample.

When performing a chi-square goodness-of-fit test,why do large values of the test statistic suggest that the variable does not have the distribution stated in the null hypothesis? Refer to the formula for the test statistic in your explanation.

A die,suspected of being unfair,was rolled 50 times.The number of times each face appeared was recorded in the following table.

A researcher performed a study to determine whether political party affiliations are different for different income brackets.She obtained the following sample data.

Research is conducted regarding the average age at retirement for four career groups.To test whether there is a relationship between age of retirement and career in these groups,700 employees,recently retired,are randomly selected.The resulting data are displayed in the contingency table below. How many degrees of freedom are there for the chi-square test statistic?

The data will be analyzed to determine if they provide sufficient evidence to conclude that an association exists between car colour and the likelihood of being in an accident.

The data will be analyzed to determine if they provide sufficient evidence to conclude that an association exists between car colour and the likelihood of being in an accident.

Suspecting that a die may be unfair,you want to investigate.To check,you roll it 90 times,recording the number of times each face appears. State your hypotheses.

160 students who were majoring in either math or English were asked a test question,and the researcher recorded whether they answered the question correctly.The sample results are given below. = 6.502;P-value = 0.011 Are the response and major independent? Use a 5% level of significance.

Research is conducted regarding the average age at retirement for four career groups.To test whether there is a relationship between age of retirement and career in these groups,700 employees,recently retired,are randomly selected.The resulting data are displayed in the contingency table below.Use a 5% level of significance. = 20.77;P-value = 0.0137

A company manager wishes to test a union leader's claim that absences occur on the different week days with the same frequencies.Are absences uniformly distributed over the week? Use a 1% level of significance.

In studying the occurrence of genetic characteristics,the following sample data were obtained.Are they uniformly distributed? Use a 10% level of significance.

Suspecting that a die may be unfair,you want to investigate.To check,you roll it 18 times,recording the number of times each face appears. If the die is fair,how many times would you expect each face to show?