Quiz_1.pdf - Statistics \u2013 Quiz 1 Fall 2020 Work alone but use any resources you want Due on September 25th email to [email protected] 1 The following

# Quiz_1.pdf - Statistics u2013 Quiz 1 Fall 2020 Work alone...

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Statistics Quiz 1 Fall 2020 Work alone but use any resources you want. Due on September 25 th email to [email protected] 1. The following data pertain to laboratory tests in a hospital. (25 Points) Shift Lab Tests Performed Day Evening Total Nonconforming 16 24 Conforming 654 306 Total 670 330 1000 a) Construct contingency tables based on total percentages, row percentages, and column percentages. b) Which percentage (total, row, or column) seems most informative? Explain? c) What conclusion can you draw from the statistics? 2. Why is it stated that the primary feature of a Pareto chart is to separate the “vital few” from the “trivial many?”(10 Points) 3. Would you consider age as a continuous or discrete variable? Why? (10 Points) 4. These are the sales tax results in \$1000 for 50 companies. (25 Points) 10.3 13.0 11.1 10.0 11.1 11.2 10.2 12.9 9.6 7.3 11.1 9.2 9.0 5.3 9.9 10.0 14.5 12.5 9.8 12.8 13.0 8.0 11.6 12.5 6.7 11.8 15.1 9.3 11.0 8.7 12.5 10.4 8.4 10.6 6.5 12.7 10.3 9.5 7.5 10.5 a) Compute the mean, variance, and standard deviation for the population. b) What percentage of companies have sales taxes between ±1, ±2, ±3 standard deviations of the mean? c) Compare your answers to the empirical rule and reach a conclusion about the data distribution. 40 960 9.3 11.5 10.7 11.6 7.8 10.5 7.6 10.1 8.9 8.6
5. Here is fuel efficiency data for several cars compiled by the owners and the government. (10 Points) Vehicle Owner Current Proposed 2005 Ford F-150 14.3 16.8 15.7 2005 Chevrolet Silverado 15.0 17.8 13.9 2002 Honda Accord LX 27.8 26.2 25.4 2002 Honda Civic 27.9 34.2 33.3 2004 Honda Civic Hybrid 48.8 47.6 36.0 2002 Ford Explorer 16.8 18.3 16.8 2005 Toyota Camry 23.7 28.5 24.2 2003 Toyota Corolla 32.8 33.1 32.7 2005 Toyota Prius 37.3 56.0 44.3 a) Compute the covariance between the “Owner” and “Current” dataHint: Look at covariance.s in Excel. b) Compute the coefficient of correlation between the “Owner” and “Current” dataHint: Look at correl in Excel c) Which is a better measure covariance or coefficient of correlation? d) What do your calculations imply about the relationship in the table? 6. What are the differences between mean, median, and mode and the advantages/disadvantages of each? (10 Points) 7. How do the empirical rule and Chebyshev rule differ? (10 Points) . .