9 terms

ch 1.2 statistics

the collection of data from every member of a population
representative sample
a sample in which the relevant characteristics of the sample members are generally the same as the characteristics of the population
design or conduct tends to favor certain results
random sample
one in which every member of the pop has an equal chance of being selected to be part of the sample
simple random sampling
every possible sample of a particular size has an equal chance of being selected
systematic sampling
using a system such as choosing every 50th member of the population
convenience sampling
we use a sample that happens to be convenient to select
cluster sampling
first divide pop into groups, or clusters, and select some of these clusters at random. then obtain the sample by choosing all the members within each of the selected clusters
stratified sampling
use this method when concerned about the differences among subgroups, or strata, within a population. first identify the strata, then draw a random sample within each stratum. total sample consists of all samples from individual strata