In 2013, 50 incidents of DUI-Liquor were reported (source: Seattle Police Department Police Report Incident database). Assume you have a list of the individuals behind the numbers, meaning the individual DUI offenders. From this list, you create a random sample of 15 DUI offenders using a random numbers table or a statistics program.
a. What are the three essential requirements for a simple random sample? Indicate and explain why these are fulfilled in the example above (DUI).
i. _______________
ii. _______________
iii. _______________
b. What is the probability of an individual DUI offender to be selected into the sample?

Question

Quizplus · Accepted Answer

The Answer is a. The requirements for a simple random sample are:
i.A defined population (all DUI offenders in the year 2013 in Seattle).
ii.An exhaustive list of all members of the population (we assume to have this list).
iii.A selection process that assures that every case or group of cases in the population has an equal chance of being selected.
b. 15/50 = 0.3
The probability of being selected is 0.3, or 30%.

In 2013, 50 Incidents of DUI-Liquor Were Reported (Source: Seattle