1 / 11

Chapter 8 Confidence Intervals

Chapter 8 Confidence Intervals. 8.3 Confidence Intervals about a Population Proportion. EXAMPLE Computing a Point Estimate

yule
Télécharger la présentation

Chapter 8 Confidence Intervals

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 8Confidence Intervals 8.3 Confidence Intervals about a Population Proportion

  2. EXAMPLE Computing a Point Estimate In a Fox News Poll conducted January 27-28, 1999, 911 registered voters nationwide were asked “Have you ever cheated on a person you were in a relationship with?” Of the 911 respondents, 191 said “yes”. Obtain a point estimate for the proportion of registered voters that have cheated on a person they were in a relationship with.

  3. EXAMPLE Constructing a Confidence Interval for a Population Proportion In a Fox News Poll conducted January 27-28, 1999, 911 registered voters nationwide were asked “Have you ever cheated on a person you were in a relationship with?” Of the 911 respondents, 191 said “yes”. Compute a 95% confidence interval for the proportion of registered voters that have cheated on a person they were in a relationship with.

  4. Sample Size Needed for a Specified Margin of Error and Level of Confidence

  5. EXAMPLE Determining Sample Size A sociologist wanted to determine the percentage of residents of America that only speak English at home. What size sample should be obtained if she wishes the estimate to be within 3 percentage points with 90% confidence assuming (a) she uses the 2000 estimate obtained from the Census 2000 Supplementary Survey of 82.4%. (b) she does not use any prior estimates.

More Related