商务统计学章节测试课后答案2024春

第八章测试

1.When a range of values is used to estimate a population parameter, it is called _______.
A:an interval estimate B:a range estimate C:a point estimate D:a statistical parameter
答案:A
2.Catherine Cho, Director of Marketing Research at Vitalglow Pty Ltd, is evaluating consumer acceptance of a new toothpaste package. Her staff report that 17% of a random sample of 200 Darwin households prefer the new package to all other package designs. If Catherine concludes that 17% of all households prefer the new package, she is using a _______.
A:a statistical parameter B:a range estimate C:an interval estimate D:a point estimate 3.The z-value associated with a two-sided 90% confidence interval is _______.
A:1.28 B:1.96 C:1.645 D:2.575 4.Suppose a random sample of 36 is selected from a population with a standard deviation of 12. If the sample mean is 98, the 99% confidence interval to estimate the population mean is _______.
A:97.35 to 98.65 B:94.08 to 101.92 C:93.34 to 102.66 D:92.85 to 103.15 5.Sam Gates, Marketing Director of Mansfield Motors’ Electrical Division, is leading a study to assess the relative importance of product features. An item on a survey questionnaire distributed to 121 Mansfield customers asked them to rate the importance of ‘ease of maintenance’ on a scale of 1 to 10 (with 1 meaning ‘not important’ and 10 meaning ‘highly important’). His staff assembled the following statistics.Ease of MaintenanceMean7.5Population Standard Deviation 1.1The 90% confidence interval for the population mean rating of ‘ease of maintenance’ is _____.
A:5.69 to 9.31 B:7.30 to 7.70 C:7.34 to 7.66 D:5.34 to 9.66 6.A researcher wants to estimate the proportion of the population which possess a given characteristic. A random sample of size 600 is taken resulting in 330 items which possess the characteristic. The point estimate for this population proportion is _______.
A:0.33 B:0.60 C:0.45 D:0.55 7.The t-distribution is similar to a normal distribution. However the t-distribution is _______.
A:discrete B:bimodal C:not symmetric D:flatter 8.In order to find values in the t- distribution table, you must convert the sample size or sizes to _______.
A:degrees of freedom B:population sizes C:z-values D:student values 9.If the degrees of freedom in a t-distribution become very large, _______.
A:the sample size must be very small B:the population size must be very large C:the t-values and the z-values are almost the same D:the sample mean approaches zero 10.In finding a confidence interval for the population mean, the population standard deviation should be used if it is known. If the population standard deviation is not known, then it should be estimated with _______.
A:the sample standard deviation B:the range C:the sample variance D:the mean