Estimating Ability with Confidence Intervals

Slides:



Advertisements
Similar presentations
To calculate a proportion from a single sample: = count of “successes” in sample sample size (n) Sample Proportions A percent out of the total sample that.
Advertisements

Confidence Intervals This chapter presents the beginning of inferential statistics. We introduce methods for estimating values of these important population.
Inference for a Population Proportion
CONFIDENCE INTERVALS HONORS ADVANCED ALGEBRA PRESENTATION 1-9.
Typical Sample Sizes Incidence Rate Calculation.
Chapter 8 Estimation: Single Population
7-2 Estimating a Population Proportion
Active Learning Lecture Slides For use with Classroom Response Systems Statistical Inference: Confidence Intervals.
Chapter 8 Confidence Intervals 8.3 Confidence Intervals about a Population Proportion.
8-1 Introduction In the previous chapter we illustrated how a parameter can be estimated from sample data. However, it is important to understand how.
1 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. Section 7.2 Estimating a Population Proportion Objective Find the confidence.
A survey found 195 of 250 randomly selected Internet users have high-speed Internet access at home. Construct a 90% confidence interval for the proportion.
INFERENTIAL STATISTICS – Samples are only estimates of the population – Sample statistics will be slightly off from the true values of its population’s.
Chapter 7 Confidence Intervals and Sample Sizes
10.1 Estimating With Confidence
Statistics: Concepts and Controversies What Is a Confidence Interval?
Chapter 7 Statistical Inference: Confidence Intervals
7-1 Estim Unit 7 Statistical Inference - 1 Estimation FPP Chapters 21,23, Point Estimation Margin of Error Interval Estimation - Confidence Intervals.
Basic Business Statistics, 11e © 2009 Prentice-Hall, Inc. Chap 8-1 Confidence Interval Estimation.
Estimating a Population Proportion. Example What is the estimate of the proportion of households tuned to the super bowl?
1 Chapter 6. Section 6-1 and 6-2. Triola, Elementary Statistics, Eighth Edition. Copyright Addison Wesley Longman M ARIO F. T RIOLA E IGHTH E DITION.
Chapter 7 Estimation. Section 7.3 Estimating p in the Binomial Distribution.
8.2 Estimating Population Means LEARNING GOAL Learn to estimate population means and compute the associated margins of error and confidence intervals.
Confidence Intervals about a Population Proportion
Population All members of a set which have a given characteristic. Population Data Data associated with a certain population. Population Parameter A measure.
Section 6.3 Confidence Intervals for Population Proportions Larson/Farber 4th ed.
Review of the Binomial Distribution Completely determined by the number of trials (n) and the probability of success (p) in a single trial. q = 1 – p If.
Confidence Interval Proportions.
Section 2 Part 2.   Population - entire group of people or items for which we are collecting data  Sample – selections of the population that is used.
CONFIDENCE INTERVALS Feb. 18 th, A STATS PROFESSOR ASKED HER STUDENTS WHETHER OR NOT THEY WERE REGISTERED TO VOTE. IN A SAMPLE OF 50 OF HER STUDENTS.
Statistical Inference: Making conclusions about the population from sample data.
Confidence Intervals feeling comfortable with error Richard Lambert, Ph.D.
In this chapter we introduce the ideas of confidence intervals and look at how to construct one for a single population proportion.
IV. Inferential Statistics B. Confidence Intervals
Confidence Intervals and Tests of Proportions. Assumptions for inference when using sample proportions: We will develop a short list of assumptions for.
Business Statistics: A Decision-Making Approach, 6e © 2005 Prentice-Hall, Inc. Chap 7-1 4th Lesson Estimating Population Values part 2.
Section 6.3 Confidence Intervals for Population Proportions Larson/Farber 4th ed1.
Working with Samples: Sample- a sample gathers information from only part of a population. Sample Proportion- is the ratio of the number of times an event.
Suppose we wanted to estimate the proportion of registered voters who are more enthusiastic about voting in this election compared to other years? Suppose.
CONFIDENCE STATEMENT MARGIN OF ERROR CONFIDENCE INTERVAL 1.
Sampling distributions rule of thumb…. Some important points about sample distributions… If we obtain a sample that meets the rules of thumb, then…
1 Chapter 6. Section 6-1 and 6-2. Triola, Elementary Statistics, Eighth Edition. Copyright Addison Wesley Longman M ARIO F. T RIOLA E IGHTH E DITION.
Confidence Intervals Chapter 6. § 6.3 Confidence Intervals for Population Proportions.
Section Estimating a Proportion with Confidence Objectives: 1.To find a confidence interval graphically 2.Understand a confidence interval as consisting.
Confidence Intervals Population Mean σ 2 Unknown Confidence Intervals Population Proportion σ 2 Known Copyright © 2013 Pearson Education, Inc. Publishing.
Chapter 19 Confidence intervals for proportions
Section 9.2: Large-Sample Confidence Interval for a Population Proportion.
Vocab Normal, Standard Normal, Uniform, t Point Estimate Sampling distribution of the means Confidence Interval Confidence Level / α.
INFERENCE Farrokh Alemi Ph.D.. Point Estimates Point Estimates Vary.
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.
8.1 Confidence Intervals: The Basics Objectives SWBAT: DETERMINE the point estimate and margin of error from a confidence interval. INTERPRET a confidence.
The Practice of Statistics Third Edition Chapter 10.3 (12.1): Estimating a Population Proportion Copyright © 2008 by W. H. Freeman & Company Daniel S.
SECTION 7.2 Estimating a Population Proportion. Where Have We Been?  In Chapters 2 and 3 we used “descriptive statistics”.  We summarized data using.
Margin of Error S-IC.4 Use data from a sample survey to estimate a population mean or proportion; develop a margin of error through the use of simulation.
Confidence Intervals Chapter 10. Confidence Intervals: The Basics Section 10.1.
 Confidence Intervals  Around a proportion  Significance Tests  Not Every Difference Counts  Difference in Proportions  Difference in Means.
Lesson 7 Confidence Intervals: The basics. Recall is the mean of the sample and s is the standard deviation of the sample. Where μ is the mean of the.
MATH Section 7.2.
CHAPTER 8 Estimating with Confidence
Confidence Intervals about a Population Proportion
A 95% confidence interval for the mean, μ, of a population is (13, 20)
Section 8.1 Day 4.
Confidence Intervals Chapter 10 Section 1.
Confidence Intervals: The Basics
CHAPTER 8 Estimating with Confidence
ESTIMATION OF THE MEAN AND PROPORTION
Chapter 8: Estimating With Confidence
Definition: Margin of Error
Chapter 8: Confidence Intervals
Presentation transcript:

Estimating Ability with Confidence Intervals

Vocabulary used in this Lesson Margin of Error Confidence Interval Sample Mean Standard Deviation

Confidence Interval An interval of plausible values where an Data point may fall An interval is better than single value because of chances of accuracy have increased

95% Confidence Intervals Three very common intervals: Interval Z-score 90% 95% 99% Interval Z-score

Interpreting Confidence Intervals About 95% of all the intervals we construct will contain the athlete’s ability “We are 95% confident that the interval of plausible values from _________ to _________ contains ____________’s ability ___________________________”

General Form for Confidence Interval

OR Margin of Error Upper Endpoint – Observed Performance Observed Performance – Lower Endpoint

Calculating a Confidence Interval for a Proportion

Calculating a Confidence Interval for a mean

Lawn Weeds A survey of 1898 adults with lawns conducted by Harris Interactive Poll found that 45% of the adults said that dandelions were the toughest weeds to control in their yards. Find the 95% confidence interval of the true proportion who said that dandelions were the toughest weeds to control in their yards.

Lawn Weeds Hence you can say with ______ confidence that the true percentage of adults who consider dandelions the toughest weeds to control in their lawns is between ___________ and _________.

Perry Como Fans Fifty-six percent of respondents to an online poll said that they were Perry Como fans. If 982 randomly selected people responded to this poll, what is the true proportion of all local residents who are Perry Como fans? Estimate at the 95% confidence level.

Perry Como Hence you can say with ______ confidence that the true percentage of________________________________________________________________is between ___________ and _________.

Continue working on examples

KNOCKOUT

1. What are the three most common confidence intervals? 10%, 100% and 1000% 90%, 95% and 99% 80%, 90% and 100% 85%, 95% and 100%

2. What is the only confidence interval we deal with in this course? 100% 99% 95% 90%

3. What is the meaning of 𝑝̂? Ability (true proportion of successes) Performance (observed proportion of successes) Sample size Confidence Interval

4. What is the meaning of 𝑝? Ability (true proportion of successes) Performance (observed proportion of successes) Sample size Confidence Interval