A | B |

Cluster Sample | two or more naturally-occurring groups of units from a sampling frame |

Complete Enumeration | all units in a population |

Convenience Sample | sample frame consists of the units easiest to obtain |

Full-Probability Sample | every unit in sampling frame has an equal probability of selection |

Simple Random Sample | every possible sample size has an equal probability of being drawn |

Stratified-Random Sample | probability samples drawn from homogenous subsets of a sampling frame. |

Systematic Random Sample | a systematic sample in which first unit drawn at random |

Systematic Sample | every nth unit in a sampling frame. |

Purposive Sample | units selected on the basis of your own judgement |

Quota Sample | selecting units on the basis of prespecified characteristics |

Snowball Sample | initial units provide additional units for study |