Can you help me to understand how to get the number 1.68??
158-1 exercise3: grapefruit bizarre The Regal Beverage Company makes the soft drink Grapefruit Bizarre. The marketing department wants to refocus its energies and resources. 158-2 exercise3: grapefruit bizarre You have been asked to determine if there are regional differences in consumer's response to advertisements for Grapefruit Bizarre. Specifically, you must find out if the Midwest responds to Grapefruit Bizarre advertisements as well as the West Coast. 158-3 exercise3: grapefruit bizarre The marketing department is clamoring to start a second campaign, It claims that ads that are effective on the West Coast do not go over as well in the Midwest. Management demands statistical evidence at a significance level of 0.05. Significance Level 0.05 Null Hypothesis Alternative Hypothesis Midwest West Coast Sample Size (n) Sample Proportion (p) 158-4 exercise3: grapefruit bizarre In the context of a free movie screening, an ad for Grapefruit Bizarre is shown to 173 Midwesterners. The viewers had been randomly selected, and had not previously tasted the drink. Significance Level 0.05 Null Hypothesis Alternative Hypothesis Midwest West Coast Sample Size (n) 173 Sample Proportion (p) 158-5 exercise3: grapefruit bizarre When asked later, 33% claimed that they were at least mildly interested in trying Grapefruit Bizarre. In a similar survey conducted on the West Coast, 42% of 152 test subjects claimed at least a mild interest in trying Grapefruit Bizarre. Significance Level 0.05 Null Hypothesis Alternative Hypothesis Midwest West Coast Sample Size (n) 173 152 Sample Proportion (p) 0.3 0.47 158-6 exercise3: grapefruit bizarre You calculate the z-value for the difference in sample proportions. Enter your z-value as a decimal number with 2 digits to the right of the decimal, (e.g., enter "5" as 5.00'). Round if necessary. Significance Level 0.05 Null Hypothesis Alternative Hypothesis158-6 exercise3: grapefruit bizarre You calculate the z-value for the difference in sample proportions. Enter your z-value as a decimal number with 2 digits to the right of the decimal, (e.g., enter "5" as 5.00'). Round if necessary. Significance Level 0.05 Null Hypothesis Alternative Hypothesis Midwest West Coast Sample Size (n) 173 15 Sample Proportion (p) 0.33 0.42 158-7 exercise3: grapefruit bizarre The z-value is + or -1.68, depending on how you set up the difference, i.e., in what order you subtract the sample means Z = ( PMid - PWC ) - (PMid - P WC ) PMic (1- PMid )- Pwe (1- Pwe ) 12 Mid = -1.68 Z = ( PC - PMid ) - (Pwc - P mid ) Pwe (1 - Pwc) - Pmid (1- PMid ) 12 Mid = +1.68 158-8 exercise3: grapefruit bizarre Question A z-value of -1.68 corresponds to a left-tail probability of 0.0465. What do you report to the marketing department? A. The p-value is 0.0930 and the data indicate that Midwesterners respond less well to the ads. 6.The p-value is 0.0930 and the data are inconclusive: the difference between the sample proportions may be due to chance. C. The p-value is 0.0465 and the data are inconclusive: the difference between the sample proportions may be due to chance. D. OThe p-value is 0.0465 and the data indicate that Midwesterners respond less well to the ads. Significance Level 0.05 Null Hypothesis Alternative Hypothesis Midwest West Coast Sample Size (n) 173 152 Sample Proportion (p) 0.33 0.42 158-9 exercise3: grapefruit bizarre You are conducting a one-sided hypothesis test, The alternative hypothesis states that the proportion of the Midwest sample is less than the proportion of the West Coast sample. Therefore, you are interested only in the left-tail probability. Your p-value is 0.0465. Significance Level 0.05 Null Hypothesis Prid 2 Pw Alternative Hypothesis mid
