Alex Dinn Larry Hedden Scott Kennedy The Coors Challenge Alex Dinn Larry Hedden Scott Kennedy

Introduction According to anecdotal accounts, many believe Keystone Light and Coors Light share a similar, if not indistinguishable, taste. However, we believe that most will in fact prefer the taste of Coors, considering it costs approximately 40% more. Our belief going into the experiment was that approximately 72% would choose Coors over Keystone, reflecting the price difference.

Procedure We asked participants to sample two cups of beer and asked the following two questions Question 1- “Can you tell the difference between the two samples?” Question 2- “Which of the two cups do you prefer the taste of?” Note- Our first question was designed to isolate those that could taste a difference since that is the population we are interested in (ie discerning tasters)

Our Null Hypothesis Our null hypothesis states that P=0.5, where P=number of tasters who preferred Coors/number of discerning tasters. Thus, the null states that test takers are equally likely to choose each type of beer. Our alternate hypothesis states that P>0.5. To reject the null hypothesis, we needed a critical value of p=0.62 for 95% confidence level. Thus, we are leaving a 5% chance of a type I error, that is we reject the null when it’s true.

Results 30 out of 51 tasters chose Coors. Thus, the test statistic we obtained was p=0.59. Therefore, we fail to reject the null hypothesis since our test statistic is below the cutoff of 0.62. Assuming the null is true, we would expect of value of a test statistic this extreme around 13% percent of the time due to chance. Thus, we suspect our null might not be true but we cannot reject the null with statistically significant results.

Power According to our belief that 72% of people would select Coors, we calculate a power of approximately 95% given our sample of 51 people. We have a 5% chance of a type II error, which means that we fail to reject the null when in fact it is false. In this case, we decide we would determine test takers are equally likely to choose each beer when in fact they are more likely to choose Coors. Given that our test statistic is just below the cutoff, power is very important. Our results lead us to believe that the true of value of P might lie somewhere in between 0.5 and 0.72. Interestingly, if our null hypothesis were p=0.72, then we would expect a value as extreme as 0.59 only 3% of the time. So we’re fairly certain the true value of P is less than 0.72 but perhaps we would need a larger power to detect such a subtle difference.

Issues that affect our results Temperature of the beer Amount of beer given to participants A choice of no preference- possibility of asking respondents to repeat the process Should we have told the test takers that they were sampling Coors Light and Keystone? Possibility of a control group- two of the same beer given to a test taker- might be difficult to interpret data? Randomness of population questionable- people over 21 Importance of Greek affiliation and gender- 57% percent of those in fraternities chose Coors and 52% of women in our sample chose Coors, leading us to believe that the effect of these demographic features might be minor.

Conclusion From our results, we fail to reject the null hypothesis at the 95% confidence level. We conclude that we do not have enough evidence to show that there is a statistically significant difference between the tastes of Coors and Keystone. However, again since our test statistic is fairly close to the cutoff, we have reason to believe that with a larger and more varied sample size, we might reject the null (ie drink more beer).