The accompanying data consists of prices ($) for onesample of California cabernet sauvignon wines thatreceived ratings of 93 or higher in the May 2013 issue ofWine Spectator and another sample of California cabernetsthat received ratings of 89 or lower in the same issue. 93: 100 100 60 135 195 195 125 135 95 42 75 72 89: 80 75 75 85 75 35 85 65 45 100 28 38 50 28Assume that these are both random samples of pricesfrom the population of all wines recently reviewed thatreceived ratings of at least 93 and at most 89, respectively.a. Investigate the plausibility of assuming that bothsampled populations are normal.b. Construct a comparative boxplot. What does it suggestabout the difference in true average prices?c. Calculate a confidence interval at the 95% confidencelevel to estimate the difference between m1,the mean price in the higher rating population, andm2, the mean price in the lower rating population. Isthe interval consistent with the statement Pricerarely equates to quality made by a columnist in thecited issue of the magazine?
Sergio Gonzalez Week 3 STATS 241 Chapter 3 Pt 2 Coefficient of variationmeasures the spread of data relative to the mean of the data used to compare variables with different mean,SD’s, and units Zscoremeasures the number of standard deviations a given data value is away from mean of data set and can be negative Ex: Mean1602 SD5000 value1810 18101602/500= .416 Empirical Ruleused to find the percentage of data within 1,2,or 3 standard deviations of them ● 68% of data in 1 SD of mean ● 95% of data in 2 SD’s of mean ● 99.7% of data in 3 SD’s of mean Percentiledata value that separates the sorted data set so that some percentage of data falls below the data value Ex: 1,1,2,3,3,6,6,6,7,7,
