Select and Draw Conclusions from Samples

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Select and Draw Conclusions from Samples

• 7.5

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Key Terms
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What is a Sample Study?
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Sample Methods
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Errors in Sampling
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Example One

• A sportswriter wants to survey college baseball
  coaches about whether they think wooden bats
  should be mandatory throughout college baseball.
  Identify the type of sample described.
• The sportswriter contacts only those coaches who
  have volunteered to be surveyed.

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Example Two

• The manager of a concert hall wants to know how
  often people in thecommunity attend concerts.
  The manager asks 50 people standing inline for a
  rock concert how many concerts per year they
  attend.
• Tell whether the sample is biased or unbiased.
  Explain your reasoning.

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Example Three

• A computer science teacher wants to know if
  students would like the morning announcements
  posted on the school's website. The computer
  science teacher surveys only those students who
  are between the ages of 20 and 25.
• Identify the type of sample described, and tell
  whether the sample is biased.

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Example Four

• A team wants to know who the fans think was the
  teams most valuable player during the season.
  Fans can vote on the teams website.

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Example Five

• The manager of a movie theater chain wants to
  find the number of movies people in the community
  usually see in a theater each month. The
  managers have the ticket sellers at each theater
  survey the customers when they purchase their
  tickets.

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HOMEWORK ASSIGNMENT

• Page 270 s 1 - 3
• Page 271 s 1 - 3