Statistics Yikes!

Why do we use statistics Summarize large numbers of responses Remember the focus group? To make comparisons Do men like RC better, or do women? To examine relationships Are greater amounts of advertising associated with higher sales?

Statistics that help to summarize Frequencies Measures of central tendency Mode Median Mean

Mode The most frequently occurring response What is the mode for this sample? Male, Male, Female, Male, Female, Male How about this sample? A, B+, A, C, D And this one? 100, 98, 94, 94, 88, 86, 86, 84, 80

Mode Mode=Male Male, Male, Female, Male, Female, Male Mode=A A, B+, A, C, D Mode=94 and , 98, 94, 94, 88, 86, 86, 84, 80 What levels of measurement are these scales?

Mode Strengths: Can be used with any level of measurement Easy to calculate and understand Bad points: Can be wildly inaccurate as an “average” There can be many modes, or none at all.

Median The point on a measure where half of the responses are above and half are below. Requires that observations can be ranked Sample A C+ B- D B Sample (ranked) A B The medianB- C+ D

Median Which observation is the middle one? If you have an odd number of observations (n), then the middle observation (after ranking) is (n+1)/2. Odd # 1, 4, 6 Observe n = 3. (3+1)/2 = 4/2 = 2 = 2 nd observation 4 is the second observation Median = 4

Median Which observation is the middle one? # observations is even, then you average the two middle observations: (n/2) and (n/2)+1 2, 4, 6, 8 (n/2) = (4/2) = 2 = second observation (n/2) + 1 = 2+1 = 3 = third observation Average of 4 (2 nd obs) and 6 (third obs) is 5 Median is 5

Median Good points Usable with any level of measurement except nominal Much better “average” than mode Good and bad point: Not sensitive to extremes or to size of scale intervals Sample 1: 1, 2, 4, 7, 10 Sample 2: 1, 2, 4, 7, 10 million

Mean Most common measure of “average” Usable only with interval or ratio measures To get a mean: sum the observations, then divide by the number of observations (n). Obs: 2,4,3,1,8,0 Sum: =18 Divide by n n=6 18/6= 3 The median? 2.5

Mean Good Points: Commonly used and understood Sensitive to scale intervals Bad Points: Cannot be used with nominal or ordinal data Can be distorted by extreme observations

Getting information from surveys SPSS is a statistical program Excel on steroids Set up like a spreadsheet

An example of data analysis

Frequencies printout in SPSS How interested are you in participating in a study abroad program while at UF? Values Frequency of occurrencePercent of occurrence

Frequencies printout in SPSS How interested are you in participating in a study abroad program while at UF? Percentages w/o missing valuesSums the percentages

Frequencies printout in SPSS How interested are you in participating in a study abroad program while at UF?

Frequencies printout in SPSS How interested are you in participating in a study abroad program while at UF?

How do we use this output?

Use frequencies to get a mean for each dimension: Low price: M = 4.67 Safety: M = 3.92 Fuel efficiency: M = 2.91 Reliability M = 4.85

How do we use this output? Problems with the output?

How do we use this output? Figure 1: Average importance ratings for car attributes Scale: 1=Not important, 5=Very important

Answering objective 1 Fact: Car buyers are most interested in reliability and low price Implication: Jetta is well-positioned to compete on reliability. The target audience should be given facts to support this: our warranty, our JD Power reliability award, our excellent review from Consumer Reports, etc. Although the Jetta is not a low price car, it is average for its class

Answering objectives 1,2, & 3 Can be done using the frequencies command if you request item means Note: you do not need to report the actual frequencies in the report, just the appendix

What do you do in your report Title page, Exec Summ, Intro (Objectives+method) Body (Subheads organized by objectives) What you found (describe statistically) What it means (your analysis) Overall conclusions Printouts in appendix

The body Report on the data analysis Use statistics and graphs to answer the objectives for the paper

Figure 1: Preferred Cola Percent responses to “My preferred brand of colas is:” Coke Pepsi RC

Figure 2: Cola preference by Gender Percent within each gender group responding to “My preferred brand of colas is:”

Implications Our data suggest two important themes: first, Coke is the brand preferred most overall, second, men show a greater preference for Coke than do women. In our view, this reinforces the need to more aggressively position Coke as a beverage for women cola drinkers.

Your implications Be helpful to the creative Remember, you are developing an advertising solution, not a marketing solution.