7.3: Confidence Intervals and Sample Size for Proportions

Slides:

Advertisements

Similar presentations

Sampling: Final and Initial Sample Size Determination

Advertisements

1 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. Section 7.3 Estimating a Population mean µ (σ known) Objective Find the confidence.

Chapter 8 Estimation: Additional Topics

Estimating a Population Proportion

Population Proportion The fraction of values in a population which have a specific attribute p = Population proportion X = Number of items having the attribute.

How to calculate Confidence Intervals and Weighting Factors

1 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. Section 7.2 Estimating a Population Proportion Objective Find the confidence.

Quiz 6 Confidence intervals z Distribution t Distribution.

7.3 Confidence Intervals and Sample Size for Proportions p = population proportion (percent) (read p “hat”) = sample proportion (percent) For a sample.

Chapter 7 Confidence Intervals and Sample Sizes

Many times in statistical analysis, we do not know the TRUE mean of a population of interest. This is why we use sampling to be able to generalize the.

8.2 - Estimating a Population Proportion

Many times in statistical analysis, we do not know the TRUE mean of a population of interest. This is why we use sampling to be able to generalize the.

Basic Business Statistics, 11e © 2009 Prentice-Hall, Inc. Chap 8-1 Confidence Interval Estimation.

Estimation Chapter 8. Estimating µ When σ Is Known.

Aim: What are the confidence intervals and samples size for proportions? Quiz Friday.

Business Statistics: A Decision-Making Approach, 6e © 2005 Prentice-Hall, Inc. Chap 7-1 4th Lesson Estimating Population Values part 2.

Section 8.2 ~ Estimating Population Means Introduction to Probability and Statistics Ms. Young.

Introduction Studying the normal curve in previous lessons has revealed that normal data sets hover around the average, and that most data fits within.

Confidence Intervals Chapter 6. § 6.3 Confidence Intervals for Population Proportions.

T T Population Sample Size Calculations Purpose Allows the analyst to analyze the sample size necessary to conduct "statistically significant"

Confidence Intervals Inferences about Population Means and Proportions.

Aim: How do we differentiate between different confidence intervals and sample sizes? Quiz Tomorrow.

Confidence Intervals for a Population Proportion Excel.

1 Chapter 12 Inferences for Population Proportions.

10.1 – Estimating with Confidence. Recall: The Law of Large Numbers says the sample mean from a large SRS will be close to the unknown population mean.

1 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. Example: In a recent poll, 70% of 1501 randomly selected adults said they believed.

Chapter 12 Inference for Proportions AP Statistics 12.2 – Comparing Two Population Proportions.

Lab Chapter 9: Confidence Interval E370 Spring 2013.

Chapter 7: Inferences Based on a Single Sample: Estimation with Confidence Interval Statistics.

SWBAT: Construct and interpret a confidence interval for a population proportion. Do Now: A confidence interval is centered around a: I. Parameter II.

Many times in statistical analysis, we do not know the TRUE mean of a population on interest. This is why we use sampling to be able to generalize the.

Review According to AAA survey Americans spend an average of 7.5 nights when they went on vacation people participated in the survey. A) Find a point.

Chapter 14 Single-Population Estimation. Population Statistics Population Statistics:  , usually unknown Using Sample Statistics to estimate population.

Chapter 6 Confidence Intervals.

Chapter 6 Confidence Intervals.

Confidence Intervals about a Population Proportion

Confidence Intervals with proportions a. k. a

Statistics Chapter 7: Inferences Based on a Single Sample: Estimation with Confidence Interval.

A Quick Review.

Statistics Chapter 7: Inferences Based on a Single Sample: Estimation with Confidence Interval.

Chapter 5 STATISTICS (PART 2).

Confidence Intervals for a Population Proportion

Statistics Chapter 7: Inferences Based on a Single Sample: Estimation with Confidence Interval.

ANATOMY OF A CONFIDENCE INTERVAL FOR m WHERE n 30

CONCEPTS OF ESTIMATION

Elementary Statistics: Picturing The World

Business Statistics, 5th ed. by Ken Black

HS 167 Test Prep Wednesday 5/23/07; 9:45 – 12:00

Section 12.2: Tests about a Population Proportion

Confidence Intervals for a Population Mean, Standard Deviation Known

Chapter 6 Confidence Intervals.

Sample Size, Margin of Error, and Confidence Intervals

Click the mouse button or press the Space Bar to display the answers.

Estimating a Population Proportion

Estimating the Value of a Parameter Using Confidence Intervals

Confidence Intervals with Proportions

ESTIMATION OF THE MEAN AND PROPORTION

Sampling results 5 (10%) 74% 10 (20%) 25 (50%) 45 (90%) Sample Size

BUSINESS MATHEMATICS & STATISTICS.

Chapter 8: Estimating With Confidence

Statistics Chapter 7: Inferences Based on a Single Sample: Estimation with Confidence Interval.

Determining Which Method to use

Chapter 12 Inference for Proportions

Inference on Proportions

Inference for Proportions

Chapter 8: Confidence Intervals

AGENDA: DG # minutes.

Inference on Proportions

First Semester Final Exam

Presentation transcript:

7.3: Confidence Intervals and Sample Size for Proportions By the end of class you will be able to calculate confidence intervals for proportions

Hershey Kisses or Diamonds? What proportion of times does a Hersey Kiss land on it’s “side” when flipped? Create a 90% confidence interval for this situation.

Some Notation: p = population proportion

The sample proportion is the best point estimate for the population proportion We will conduct 20 trials to get a sample proportion

Proportion Confidence Interval Standard Deviation: Error: CI:

On Calculator: Menu Statistics Confidence Intervals 1PropZ Interval

A sample of 500 nursing applications included 60 men A sample of 500 nursing applications included 60 men. Find the 90% confidence interval of the true proportion of men who applied to the nursing program.

In a sample of 80 high school students, 90% believe that they should be exempt from final exams. Find a 95% confidence interval for students who believe in exam exemptions.

Determining Sample Size According to a prior study .169 is the proportion of people that rent beach umbrellas in Ocean City. How many beachgoers should be surveyed about umbrella rentals in order to be 90% confident that the sample percentage is in error by no more than 4 percentage points?

Determining Sample Size-Solve for n Always round up to ensure the sample size is large enough!

If no approximation of the sample proportion is known, use .5 for p-hat. This will guarantee that the sample size is large enough

Determining Sample Size How many beachgoers should be surveyed about umbrella rentals in order to be 90% confident that the sample percentage is in error by no more than 4 percentage points? No prior sample exists