Statistics questions
1.When is the median a more appropriate central tendency statistic than the mean? Provide an example. (2 points)
2.If you had to guess the category of a nominal variable that best represents the variable’s distribution — and you have no information other than a simple frequency table — which category would you choose? Why? (2 points)
3.Referring to the formulas for the standard deviation (s) and variance (s2):
Why do researchers more frequently report the standard deviation? (1 point)
4.Why is the range a less effective measure of dispersion for interval-level variables than variance or standard deviation? (2 points)
5.Whenever possible, it is preferable to use interval measures as opposed to ordinal measures. Why? (1 points)
6.To produce effective quantitative research, we need measures that are both valid and reliable. What does this mean? (2 points)
7.Statistically speaking, why does the casino always win in the long run? (2 points)
8.A researcher is interested in establishing a causal relationship between two variables. What general conditions would need to exist between the variables for her assertion about causality to be realistic? (3 points)
9.Why are z-scores important in statistical analysis? (1 point)
10.A researcher draws a random sample of adult Tucsonans in order to measure how much money individuals are saving per month. Given the current economic situation, many in the policy-making world are calling for more data on individual savings. She finds that the distribution for savings/month has a slight positive skew (i.e. not normally distributed). Assuming her sample size is reasonable, why do we have any confidence that her sample mean (mean savings/month) might be a reasonable estimate of the true population mean? (2 points)
