Lecture11

# Lecture11 - Lecture 11 Compared to what? Hypothesis test...

This preview shows pages 1–11. Sign up to view the full content.

1 Lecture 11 Compared to what? Hypothesis test  for a proportion

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 Overview • You’ve learned hypothesis tests for a mean • Today you’ll learn hypothesis tests for a proportion • Connection A proportion is the mean of a dummy variable
3 1. What are the hypotheses?

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
4 Research question • Who will win Ohio? • Bush or Kerry?
5 Parameter • Hypothesis = Claim about a  parameter Today: claim about the population proportion π . E.g., proportion of voters that favors Bush Population: Voters choosing Bush or Kerry need a majority to win the state • Two alternatives:  winning.) is Kerry or Bush (Either .5. not is Bush voting proportion that the ) : ( is ) ( hypothesis research The 5 . : tied.) is (Ohio .5. is Bush voting proportion that the ) : ( is ) ( hypothesis null The 5 . : 1 1 0 0 π H H H H = One tail or two?

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
6 2. Hypothesis tests
7 Hypothesis test: Definition • Given evidence from a  sample , we test (decide whether to reject) the null hypothesis about the population

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
8 Sample • RasmussenReports.com • Sample of 500 Likely Ohio Voters, March 14-16, 2004 Bush 41%, Kerry 45%, Other 4%, Not Sure 10% Ignore “other”, “not sure” Remaining: N =430, p =.477 favor Bush, 1- p =.523 Kerry • Most of the  sample  favors Kerry But the hypothesis asks about the population which is probably different (sampling error)
9 2a. Hypothesis test: Sampling distribution method

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
10 Hypothesis test: Sampling distribution method If H 0  were true what would the sampling distribution look like (null distribution)? Where would your sample fall in the null distribution?
This is the end of the preview. Sign up to access the rest of the document.

## This document was uploaded on 06/01/2011.

### Page1 / 31

Lecture11 - Lecture 11 Compared to what? Hypothesis test...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online