Sampling Strategies (Alg 2)

Biased Samples

1. Self Selected 2. Convenience

simple random sample (BEST)

All members have equal chance of being selected. - look for the word *RANDOM*

CLASSIFY: A hospital wants to survey religious participants in their city about what they seek from a hospital chaplain, so they randomly select 555 religious meetings in the city and survey every participant in those meetings.

Cluster

Systematic Sample

Members are chosen in pattern such as every other person. - look for *Every nth person*

stratified sample

People are divided into groups. Members are randomly chosen from each group ("teams or groups") - EX1: out of 3 groups, 1 person from group 1 is selected, 2 people from group are selected, and 3 people from group 3 are selected. - EX2: 10 players from each each of the 32 teams are chosen.

Cluster Sample

Population is divided into groups. A sample of the groups is randomly chosen. ALL members of the chosen groups are surveyed. ("Teams or groups") EX: Survey EVERY sophomore and senior in a high school

self selected sample

members *volunteer* to participate

convenience sample

only members of the population who are easily accessible are selected