Populations, Samples and Sampling

Question 1

Populations

Answer 1

universe of events

Question 2

Samples

Answer 2

subset drawn from a population

Question 3

Random

Answer 3

Definition - every subject has the same probability of being selected as the next subject, subjects selected using a table of random numbers, flip of a coin, drawing straws, etc

Question 4

Systematic

Answer 4

Definition - a predetermined method is established and used to select subjects

Examples - choose every 3rd subject, choose every 4th subject, choose odd numbered subjects, etc.

Question 5

Stratified

Answer 5

Definition - use random or systematic sampling to select subjects belonging to different strata: males versus females, adult versus immature stages of the life cycle, etc.

Question 6

Convenience

Answer 6

Definition - use whatever sample is convenient to obtain under whatever financial constraints apply, etc.

Question 7

Parameters

Answer 7

numbers obtained from populations (measures of central tendency or variation), used to summarize the numerical characteristics of the population

Question 8

Statisitcs

Answer 8

numbers obtained from samples drawn from populations, used to estimate population parameters

Question 9

Probability

Answer 9

the chance or likelihood that an event will occur

Question 10

empirical method

Answer 10

calculate the probabilities based on data collection