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Statistics: Stratified Sampling
by Texas Instruments

Published on October 05, 2011


  • Students will be able to identify situations in which stratification might reduce variation.
  • Students will recognize that some stratification designs are useful in reducing variation and some are not.
  • Students will recognize that random selection of subject(s) must occur within each stratum.
  • Students will recognize that the subjects within each stratum should be as similar as possible and different from the subjects in the other strata based on a variable that has the potential to affect the outcome of the study.


  • random selection
  • simple random sample (SRS)
  • stratified random sample
  • stratum(a)
  • survey

About the Lesson

This lesson involves determining which of three different sampling methods - a simple random selection design and two stratified selection designs - would be most beneficial in selecting a survey sample within a given context.
As a result, students will:

  • Use a simple random sample (SRS) to select survey participants.
  • Use two different stratified random sampling designs to select survey participants.
  • Compare means and variability for the three sampling designs to determine the most effective design for this context.