Day

to

Day

Politics

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2)
How is this Poll Average calculated?
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3) Why is this Poll Average better?
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5)
What determines if the state is a toss up?**

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6)
What determines if the state supports the candidate?**

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7) How are the battleground state probabilities calculated?**

Candidate A has an estimated percentage of support of 49%.
If the margin of error is 3%, then we have 95% confidence that the
candidate’s percentage of support in the population is between 46% and 52%.

**
How is this Poll Average calculated?**

The
*Day to Day Politics Poll Average* uses the statistically correct
method for conducting a poll average. It utilizes the number of people
conducted in each poll to accurately reflect the information of each poll
instead of treating each poll with the same weight. A poll conducted
on 100 people should not have the same weight as a poll conducted on 3000
people as other poll averages do. Thus, the
*Day to Day Politics Poll Average*
has several advantages over other poll averages. First, it properly
gives more weight to larger polls, since they more accurately reflect the
population average. Second, the *
Day to Day Politics Poll Average* statistically has a margin of error,
which reveals the measure of uncertainty in the Poll Average, just as the
margin of error in a single poll measures the uncertainty of that poll.

Finally, the Poll Average
is conducted on the last week to 10 days, but any more than that would not
accurately reflect the changing views of many Americans.

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Why is this Poll Average better?
**

This poll average
correctly combines different polls based on their different samples sizes
and gives more weight to polls that have larger sample sizes, since those
polls have smaller ranges of uncertainty.
Also, this Poll Average has a margin of error, which gives us the
range in uncertainty around the estimated percentages of support.
The Poll Average usually has a margin of error of less than 1%, which
means we can more accurately estimate the percentage of support within the
population than any single poll or other types of poll averages.

The margin of error
tells us that we have 95% confidence that a candidate's estimated percentage
of supporters falls within plus or minus 1 margin of error.
For example:

Candidate A has an estimated percentage of support of 49%.
If the margin of error is 3%, then we have 95% confidence that his
percentage of support in the population is between 46% and 52%.

**
What determines if a state is a toss up?**

A state is considered a toss up if after we analyze the polls for that
state, there is less than a __95% probability__ that any candidate will
win the state.

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What determines if a state supports
the candidate?**

A state is considered supporting the candidate if after we analyze the polls
for that state, there is more than a __95% probability__ that the
candidate will win that state.

**
How are the battleground state probabilities calculated?**

The polls for a state are collected over the previous 1-2 weeks and the
election within that state is simulated 50,000 times from those polls.
Then the number of times the candidate wins the election in those
simulations is divided by 50,000 and the probability is reported.

**Technical note**:
What is taking place here is we are treating the polls as multinomial
distributions and using WinBugs to sample from the posterior distribution.
Then we estimate the probability that candidate A’s support is
actually greater than candidate B’s support)