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Provide an appropriate response. 1)A set of data consists of the number of years that applicants for foreign service jobs have studied German and the grades that they received on a proficiency test. The following regression equation is obtained: = 31.6 + 10.9x, where x represents the number of years of study.
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21) When working for the Brooklyn District Attorney, investigator Robert Burton analyzed the leading digits of the amounts from 784 checks issued by seven suspect companies. The frequencies were found to be 0, 12, 0, 73, 482, 186, 8, 23, and 0, and those digits correspond to the leading digits.
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Given below are the analysis of variance results from a Minitab display.  Assume that you want to use a 0.05 significance level in testing the null hypothesis that the different samples come from populations with the same mean. 1)Identify the value of the test statistic. Source   DF   SS   MS   F   p Factor    3  .
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10) Discuss the three characteristics of a chi-square distribution. Perform the indicated goodness-of-fit test. 11) A company manager wishes to test a union leader's claim that absences occur on the different week days with the same frequencies. Test this claim at the 0.05 level of significance if the following sample data have.
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Solve the problem. 21)When performing a hypothesis test for the ratio of two population variances, the upper critical F value is denoted FR.  The lower critical F value, FL , can be  found as follows:  interchange the degrees of freedom, and then take the reciprocal of the resulting F value found.
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10)Describe what scatterplots are and discuss the importance of creating scatterplots. Use computer software to find the best multiple regression equation to explain the variation in the dependent variable, Y, in terms of the independent variables, X1, X2, X3. 11)YX1X2      98.6 87.4 108.5     101.2 97.6 110.1     102.496.7110.4CORRELATION COEFFICIENTS     100.998.2104.3     102.399.8107.2  Y/.
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7) Use the sample data below to test whether car color affects the likelihood of being in an accident. Use a significance level of 0.01.                                                    Red Blue White Car has been in     accident283336 Car has not been       in accident232230 Provide an appropriate response. 8) Describe the null hypothesis for the.
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9) Provide an appropriate response. Control Chart Constants xsR        n    A2    A3       B3    B4       D3    D4 2 1.880 2.659   0.000 3.267   0.000 3.267 3 1.023 1.954   0.000 2.568   0.000 2.574 4 0.729 1.628   0.000 2.266   0.000 2.282 5 0.577 1.427   0.000 2.089   0.000 2.114 6 0.483 1.287   0.030 1.970   0.000 2.004 7 0.419 1.182   0.118 1.882   0.076 1.924 8 0.373 1.099   0.185 1.815   0.136 1.864 9 0.337 1.032   0.239 1.761   0.184 1.816 10 0.308 0.975   0.284 1.716   0.223 1.777 10).An x chart based on standard deviations (instead of ranges)  is made by plotting sample                                                                                   means with a.
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Find the critical value. Assume that the test is two-tailed and that n denotes the number of pairs of data. 11)n =20, α = 0.01 A) -0.570B) 0.570C) ±0.447D) ±0.570 Use the rank correlation coefficient to test for a correlation between the two variables. 12)A placement test is required for students desiring to.
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Given below are the analysis of variance results from a Minitab display.  Assume that you want to use a 0.05 significance level in testing the null hypothesis that the different samples come from populations with the same mean. 19)Identify the p-value. Source   DF   SSMS   F   p Factor   3      13.500   4.500   5.17   0.011 Error   16  .
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Provide an appropriate response. 6)Describe the standard error of estimate, se. How do smaller values of se relate to the dispersion of data points about the line determined by the linear regression equation? What does it mean when se is 0? Given the linear correlation coefficient r and the sample size n,.
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4) Describe a goodness-of-fit test. What assumptions are made when using a goodness-of-fit test? 5) The following table shows the number of employees who called in sick at a business for different days of a particular week.                Day   Sun  Mon Tues Wed Thurs Fri Sat Number sick   8   12    7    11    .
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Solve the problem. 1) A researcher wishes to test whether the proportion of college students who smoke is the same in four different colleges. She randomly selects 100 students from each college and records the number that smoke. The results are shown below. College A College B College C College D Smoke17261134 Don't.
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7) Why do researchers concentrate on explaining an interaction in a two-way ANOVA rather then the effects of each factor separately? 8) The following data contains task completion times, in minutes, categorized according to 8) the gender of the machine operator and the machine used. Male  Female Machine 1   15, 17 .
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14)Which of the following distribution-free tests has the lowest efficiency rating compared to its  parametric counterpart? A) Kruskal-Wallis testB) Wilcoxon rank-sum test C) Wilcoxon signed-ranks testD) rank correlation test Use the sign test to test the indicated claim. 15)An instructor gives a test before and after a lesson and results from randomly selected  students.
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Use computer software to find the best multiple regression equation to explain the variation in the dependent variable, Y, in terms of the independent variables, X1, X2, X3. 20) YX1X2 151.216 151.216 171.016CORRELATION COEFFICIENT 60.89 10.11Y/ X1 = 0.886 80.88Y/ X2 = 0.965 100.810 171.016COEFFICIENTS OF DETERMINATION 151.215 110.79Y/ X2 = 0.932 181.418Y/ X2, X1 = 0.943 161.015 100.89 70.55 181.116       ^        ^ A) Y = 0.42.
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21)For the data below, determine the value of the linear correlation coefficient r between y and x2.  x 1.2   2.7   4.4  6.6   9.5 y 1.6  4.7   9.9  24.5   39.0 A) 0.913B) 0.985C) 0.990D) 0.873 Construct a scatterplot and identify the mathematical model that best fits the data.  Assume that the model is.
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Solve the problem. 16) A researcher wishes to test the effectiveness of a flu vaccination. 150 people are vaccinated, 180  people are vaccinated with a placebo, and 100 people are not vaccinated. The number in each group who later caught the flu was recorded. The results are shown below.              16)             Vaccinated.
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11) Describe a goodness-of-fit test. What assumptions are made when using a goodness-of-fit test? Solve the problem. 12) Use a 0.01 significance level to test the claim that the proportion of men who plan to vote              in the next election is the same as the proportion of women who plan to.
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Provide an appropriate response. 2) Describe the Wilcoxon signed-ranks test. What types of hypotheses is it used to test? What assumptions are made for this test? Use a Kruskal-Wallis test to test the claim that the samples come from populations with equal medians. 3)Listed below are grade averages for randomly selected students with three.
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Choose the one alternative that best completes the statement or answers the question. 11)Which of the following statements concerning the linear correlation coefficient are true? I: If the linear correlation coefficient for two variables is zero, then there is no relationship between the variables. II: If the slope of the regression line is.
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4) Explain the computation of expected values for contingency tables in terms of probabilities. Refer to the assumptions of the null hypothesis as part of your explanation. You might give a brief example to illustrate. Perform the indicated goodness-of-fit test. 5) You roll a die 48 times with the following results. Number 1    2.
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21) The following data contains task completion times, in minutes, categorized according to the gender of the machine operator and the machine used.                     Male Female Machine 1 15, 17  16, 17 Machine 2 14, 13  15, 13 Machine 3 16, 18   17, 19 The ANOVA results lead us to conclude that the completion.
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20) Ten luxury cars were ranked according to their comfort levels and their prices. Find the rank correlation coefficient and test the claim of correlation between comfort and price. Use a significance level of 0.05. Use a Kruskal-Wallis test to test the claim that the samples come from populations with equal medians. 21)The.
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15) The table below shows the age and favorite type of music of 668 randomly selected people.        Rock Pop Classical 15-25   508573 25-35  689160 35-45  907477 Use a 5 percent level of significance to test the null hypothesis that age and preferred music type are independent. Perform the indicated goodness-of-fit test. 16) In studying the.
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Provide an appropriate response. 13) Describe the test of homogeneity. What characteristic distinguishes a test of homogeneity from a test of independence? 14) A survey conducted in a small business yielded the results shown in the table.                                                          Men Women                  Health insurance      41     22            No health insurance      34     24 i)  Test the claim.
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Test the claim that the samples come from populations with the same mean. Assume that the populations are normally distributed with the same variance. 13)At the 0.025 significance level, test the claim that the four brands have the same mean if the following sample results have been obtained. Brand ABrand BBrand CBrand.
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Provide an appropriate response. 1)List the advantages and disadvantages of nonparametric tests. 2)11 runners are timed at the 100-meter dash and are timed again one month later after  following a new training program. The times (in seconds) are shown in the table. Use Wilcoxon's signed-ranks test and a  significance level of.
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