## Lesson 18: Forecasting the 2017 Virginia Governor’s Race

November 6, 2017

Review:

- Inference for Proportions

Presentation:

- Virginia Governor’s Race
- Candidates
- Ed Gillespie (Republican)
- Ralph Northam (Democrat)
- Cliff Hyra (Libertarian)

- Significance

- Candidates
- Understand relationship with techniques from

Assignment:

- Read today’s Analysis from Real Clear Politics
- Study the 2013 Virginia Gubernatorial election. Which polls did best 4 years ago?
- Select
**ten (10) polls**from the list at Real Clear Politics- Choose polls you believe will provide the most accurate data

- For each of your selected polls, find the following:
- What is the reported % vote estimate for each of the two major party candidates?
- What is the reported margin of error?
- What is the reported sample size?

**Produce your own 95% confidence interval**to estimate vote % for both major candidates.- Extract data necessary to produce your own calculations
- you’ll need to calculate
*p-hat*and*s (s*tandard deviation) - hint:
- if
*n = sum of sample sizes, then s = √(p*(1-p)/n)* *if n = 10, then s = √(ε(x-x-bar)^2/n-1)*

- if

- you’ll need to calculate
- Clarify how you’re using the polling data
- Note any assumptions you have to make to facilitate calculations
- Round point estimates and margins of error to the nearest 3 digits (
*e.g., 0.466 ± 0.034*)

- Extract data necessary to produce your own calculations
**Write 4 brief paragraphs**discussing your analysis and predicting the election outcome- How did you select your sample polls? What was your criteria?
- Describe your calculations – how did you use the polling data to generate your estimate?
- What is your predicted outcome for the election? Who do you think will win and why?
- How does your opinion differ from today’s Analysis from Real Clear Politics?