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Testing Claims About Proportions. In Exercises 9–32, test the given claim. Identify the null hypothesis, alternative hypothesis, test statistic, P-value, or critical value(s), then state the conclusion about the null hypothesis, as well as the final conclusion that addresses the original claim. Use the P-value method unless your instructor specifies otherwise. Use the
16. Drug Screening The company Drug Test Success provides a “1-Panel-THC” test for marijuana usage. Among 300 tested subjects, results from 27 subjects were wrong (either a false positive or a false negative). Use a 0.05 significance level to test the claim that less than 10% of the test results are wrong. Does the test appear to be good for most purposes?
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ESSENTIALS OF STATISTICS 6TH ED W/MYSTA
- MATH STATISTICS Part 4. 1. Examine the data set below that represents a sample. F.) the first, second and third quartiles; G.) the interquartile interval; H.) the standard deviation of the sample; I.) The variance of the sample.arrow_forwardLINEAR REGRESSION 2) During the last three months, on 10 occasions a sound equipment store appeared in television commercials to promote your sales. The managers want to investigate whether there is a relationship between the number of commercials broadcast on the weekend and the sales in the following week according to the table (img1) A. What are the mean and median of each distribution? B. What is the variance and standard deviation of each distribution? C. Make the scatterplot, calculate the covariance and discuss it D. Calculate Pearson's correlation coefficient. Is it consistent with covariance? Comment it.arrow_forwardStatistics students believe that the mean score on a first statistics test is 65. The instructor thinks that the mean score is higher. She samples 10 statistics students and obtains the scores: Grades 69 69 63.9 68.4 62.7 73.5 73.5 64.3 Test grades are believed to be normally distributed. Use a significance level of 5%. A. State the alternative hypothesis: HA: Ομ 65 B. State the mean of the sample: C. State the standard error of the sample means: D. State the test statistic: t = E. State the p-value: F. Decision: O Fail to reject the null hypothesis. Reject the null hypothesis. 73.5 96arrow_forward
- Point ENTRY CARD Compute the variance of this frequency distribution. Score Number of Students 3. 8 10 4 12 15 Follow the steps given below. Complete the tables shown for each step. Steps 1. Compute the mean by using the Solution Number of formula X=EX Score %3D Students fX 3 8. 10 4 12 15 3 n= 20arrow_forwardStatistics students believe that the mean score on a first statistics test is 65. The instructor thinks that the mean score is higher. She samples 10 statistics students and obtains the scores: Grades 96 96 66.5 68.4 62.7 62.7 61.9 73.5 73.5 85.5 Test grades are believed to be normally distributed. Use a significance level of 5%. A. State the alternative hypothesis: H: Ou 65 B. State the mean of the sample: (Round to two decimal places.) C. State the standard error of the sample means: (Round to four decimal places.) D. State the test statistic: t = (Round to four decimal places.) E. State the p-value: (Round to four decimal places.) F. Decision: O Do not reject the null hypothesis. O Reject the null hypothesis. dese > Next Questionarrow_forwardDetermine the variance and standard deviationof each random variable.arrow_forward
- Engineering data analysis show solutionarrow_forwardWhen data is said to be binomial, this means that ___________. a. They will always be normally distributed b. There are only 2 sets of data c. There are only 2 categories in which a measurement could possibly belong d. The data is classified into 2 or more categoriesarrow_forwardDoes the Normal Probability plot look linear and do we use the t-procedure?arrow_forward
- Explain why the t-distribution has less spread as the number of degrees of freedom increases.arrow_forwardInstruction: Reflect on the question below and write your response on your journal. 1. When do we use t-distribution? 2. How applicable is it in real situations?arrow_forwardPART VI. Consider the following discrete probability distribution. X P(x) 0 0.18 1 0.44 2 0.27 3 0.08 4 0.03 1. Calculate the mean or the expected value of X 2. Calculate the variance of the random variable, X 3. Calculate the standard deviation of the random variable, Xarrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill