GSE Math 78 Unit 2 – Inferences Notes

Sampling Lesson

Date ______

Sampling Vocabulary:

Survey

  • a study of one or more ______of a ______

Population

  • the ______you want information about

Sample

  • a ______of the population

Unbiased Sample

  • a sample that ______reflects the characteristics of a population

Biased Sample

  • a sample that is ______of the population; one or more parts of the population are favored over others

Unbiased Samples:

Simple Random Sample

  • every member of the population has an ______chance of being selected

Stratified Random Sample

  • population is ______into ______groups – members are selected at random

Systematic Random Sample

  • a ______is used to select members of the population; items or people are selected according to a specific time or item interval

Biased Samples:

Convenience Sample

  • only members of the population who are ______accessible are selected

Voluntary Response Sample (Self-Selected Sample)

  • members of the population select ______by ______

Group Discussion Questions ______:

  1. John surveys every fifth person leaving a pet supply store. Of those surveyed, ¾ support the city manager’s proposition to tear down the old library and replace the area with the construction of a new pet park. John plans to write a letter to the editor of the local newspaper about the proposal for the new pet park stating that there is tremendous support from the citizens of the town for constructing a new pet park.
  2. Can the conclusion John stated be accurately supported?
  1. What are other alternatives for obtaining a good sample of the population?
  1. I want to know the average height of students at Hillgrove High School. What would be a good method to find this number without checking every student?
  1. Your school is conducting a survey on a proposed dress code. The first 20 students entering the school in the morning are surveyed. What type of sampling method is used?

GSE Math 78 Unit 2 – Inferences Notes

  1. convenience
  2. random
  3. stratified random
  4. systematic

CCGPS Math 7 Unit 4 – Inferences Day 1 Notes

  1. A principal is surveying the parents of his school to find out if they support extending the school day by 20 minutes. Which of the following methods of choosing a sample will most likely result in a sample that is representative of all parents?
  1. Surveying all the parents at a parent – teacher meeting
  2. Surveying 50 parents of 9th grade students
  3. Surveying all the parents who volunteer for a school fundraiser
  4. Selecting every 20th name from an alphabetical list of all parents and surveying those parents.
  1. CIRCLE the following question(s)that are not potentially biased.
  1. Do you prefer creamy macaroni and cheese or bland rice?
  2. Don’t you feel the city is wasting money by building that new stadium?
  3. Do you prefer shopping online or in the stores?
  4. Don’t you agree that the driving age should be raised to 18 to decrease the number of accidents?