580 Chapter 11 inference for Relationships between categorical and Quantitative

Question

580 Chapter 11 inference for Relationships between categorical and Quantitative variables 11.71 A car buyer wanted to compare prices of 3.year-old BMw and Mercedes Benz automobiles, and found these prices (in thousands of dollars) listed in the classified ads: 32 35 29 33 35 42 35 47 53 BMW 27 54 27 27 34 32 28 51 28 Mercedes 26 47 32 39 a. Use software to produce sample means and standard deviations of prices. populations that b. standard deviations similar enough that we can assume they arise from Are the share the same standard deviation? variances) c. Use software to out a pooled two-sample t test (assuming equal population carry report the test statistic t and the P-value. population d. Use software to carry out an ANOVA (F test, which requires the assumption of equal variances; report the test statistic F and the P-value. e. If sample sizes and standard deviations are equal, the F statistic is in fact the square of the two- sample t statistic. Find the square of your t statistic from part (c), and comment on whether or not it is about the same as the F statistic. f. Comment on whether or not the P-values are similar for the pooled two-sample test compared to the ANOVA (F) test. g. Comment on whether or not the P-values would be similar if the two-sample test had been carried out with a one-sided instead of two-sided alternative.

Explanation / Answer

a. Answer:

b. Answer:

The standard deviations are similar enough that we can assume they arise from populations that share the same standard deviations. For BMW is 9.0 and Merceds is 9.1. So, there is no much difference in SDs.

c. Answer:

d. Answer:

BMW Mercedes Mean 35.9 36.0 Standard Error 2.1 4.5 Median 34.0 35.5 Mode 35.0 0.0 Standard Deviation 9.0 9.1 Sample Variance 81.5 82.0 Kurtosis -0.2 -1.1 Skewness 1.0 0.3 Range 27.0 21.0 Minimum 27.0 26.0 Maximum 54.0 47.0 Sum 683.0 144.0 Count 19.0 4.0

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.