Friday, February 12, 2016

NH Exit Poll: Dems Divided, Trump Voters United

The New Hampshire primary was a resounding victory for Bernie Sanders and Donald Trump.  Their wins clearly show a dissatisfaction with the party establishment but the exit polls show different demographic patterns for their support.

Democratic Primary

The generation gap between older and younger voters for Sanders has been well reported but there are other divides.  Sanders won 61% of the white vote and 50% of the nonwhite vote (they were 7% of the electorate in NH).  Sanders won all education levels with 60% or more all education levels except for a lower % of the vote among post-graduates at 51% to 48% for Clinton.  

He won every income level except those earning more than $200,000 or more (8% of NH Dem voters) with 53% for Clinton.  Sanders had 60% or more of the income categories earning less than $100,000.

Sanders won 52% of voters who were registered Democrats and 73% of independents.  He won 67% of unmarried voters and 56% of married voters.  What gender is crossed with gender Sanders did equally well with married men and women with 56% support from each.  Sanders won 74% of unmarried men and 62% of unmarried women.  

The top issues among democratic voters were economy/jobs (33%), income inequality (32%), and health care (23%) followed by terrorism (9%).  Sanders won among each of these issues with the lowest share among those who name terrorism where he garnered 50%. 

63% of Dem voters said that they support a single payer health care system while 32% said that they did not.  Sanders won 71% of those who support it while Clinton won 58% of those who oppose.  Sanders won 61% of those who said that the debates were a factor in deciding who to vote for while winning 54% among those who did not.

GOP Primary

The most remarkable thing to say about the Republican primary is how homogeneous it is.  Trump won 38% of male voters and 33% of female voters which was the highest for both genders.  Trump won all age groups with 30% or more of the vote.  Trump finished first among all education levels with 47% of those with high school or less, 39% of those with some college, 33% of college graduates, and 25% of those with post graduate degrees.  Trump finished first among all income levels.  Trump did equally well among independents and registered Republicans.

The sharpest divide among voters appeared to be among issues.  Trump did better among gun owners (40%) than non-gun owners (28%) but finished first among both.  Trump did better among non-evangelical Christians (38%) than evangelicals (27%) but finished first among both.  

The top issues for the GOP voters were 33% economy/jobs, 26% government spending, 24% terrorism, and 15% immigration. Trump won all 4 issue groups with the strongest support among those stating immigration being strongest for Trump (53%) and those stating terrorism (29%) being the weakest.

Third place finisher Ted Cruz won among voters who stated 'shares my values' as the top candidate quality (21%) while Trump won among those who stated electability (33%), tells it like it is (66%), and can bring change (37%).  Trump won among those who were very worried about the economy (39%) while second place finisher John Kasich barely won among those who were somewhat worried (27%).  

65% of voters supported Trump's proposal on banning Muslims entering the US while 32% did not.  Trump had 45% of those who supported his proposal while Kasich had 26% of those who did not.  

New polls suggest that Clinton and Sanders are tied in Nevada and Trump is leading in South Carolina which are the next contests for the parties on Feb. 20.  If similar patterns are seen in the entrance poll in Nevada and in the exit poll in SC it could be another good night for Trump and Sanders.

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Monday, February 8, 2016

Iowa Coin Toss Math Part 2

I received a lot of comments on my post on the probability of Hillary Clinton winning all six coin tosses in a tied caucus site is 1 in 64 or 1.56% or 0.0156 as the Des Moines Register reported.  NPR cited an unnamed Democratic party official saying that there were a dozen coin tosses and Sanders won "at least a handful" while other media outlets and the Sanders campaign have repeated the claim that there were six.   Someone sent me the above video which appears to show Sanders winning a coin toss.

Lets be conservative and say that there were seven coin tosses with Sanders winning one.  What is the probability of this outcome?  According to the binomial distribution, the probability of exactly one success out of seven coin tosses (with the chance of success on 1 toss being 0.5) is 0.0547 or 1 in 18.28.  The probability of 1 or fewer successes is 0.0625 or 1/16.  

If we take the democratic official at his word that he won "a handful" out of a dozen tosses (we will call a handful 5), the probability of exactly 5 successes in 12 tosses is 0.1934 or about 1 in 5.  The probability of 5 or fewer successes in 12 tosses is 0.381 or 38.7% or 1 in 2.58 tosses.  

The probability in the first two scenarios is low but there is a greater chance of these scenarios than dying in a plane crash (1 in 5.4 million), being struck by lightning in one's lifetime (1 in 12,000), or the probability of winning the Powerball jackpot (1 in 175,223,510).  The Des Moines Register still says that there were irreguarities in the caucus process and that the gap between Clinton and Sanders narrowing to 700.47 state delegates for Clinton and 696.92 for Sanders.  

Hopefully New Hampshire;s primary won't have the same issues.  Other states do have caucuses similar to Iowa.  Voting or caucusing irregularities are usually noticed when the results are as close as Iowa this year or Florida in 2000.  Results that are independently verifiable is the key.

**Related Posts**

Iowa Caucus Coin Toss Math


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Wednesday, February 3, 2016

Iowa Caucus Coin Toss Math

The 2016 Iowa Caucuses had a fantastic photo finish.on Monday night with Hillary Clinton outlasting Bernie Sanders by 4 delegates to the states county conventions.  The delegates to the county conventions are allocated to the candidates based on the percentage of the caucus goers supporting a viable candidate.  A candidate is viable is he or she has more than 15% of the caucus goers present.  In the caucus room there is a scramble for unviable candidates caucus goers (in this case Martin O'Malley and uncommitted supporters) too go into either Clinton or Sanders corner.  

For caucuses the networks do entrance polls of caucus goers rather than exit polls for primary and general elections.  The entrance poll tells us about who the goers are and what they were thinking as they enter the caucus room with a random sample of 1660 out of over 100,000 total goers.  The table below shows the breakdown of democratic caucus goers by gender.  Multiplying the marginal percentages for gender by the cell percentages for the candidates and then summing across columns gives the preferences of goers as they entered the room.  For example the overall % for Sanders is found by the formula 0.50*0.43 + 0.42*0.57 = 0.4544 or 45.44%.  The final delegate total suggests that the Sanders people did a better job attracting O'Malley and uncommitted caucus goers into their corner than Clinton once they were in the room.  The rest of the exit poll shows that Sanders was preferred overwhelmingly by younger goers, by those with some college or a college degree, by single goers, and by low income caucus goers.

Men (43%)
Women (57%)
% Caucus Goers on Entrance
Final Delegates (%)
701 (49.86%)
8 (0.6%)
697 (49.57%)
0 (0%)

In cases where there was a tie in the caucus room, the winner is determined by a coin toss.  For example in the case of a tie for a room with 5 delegates, 2 delegates would be awarded to Sanders, 2 to Clinton, and the 5th delegate awarded to a candidate by a coin toss.  On Monday night there were 6 caucus rooms decided by a coin toss with all 6 delegates being awarded to Clinton.  Given that the margin of victory was 4 delegates for Clinton it seems that that is what determined the outcome.  The Nightly Show with Larry Wilmore had a funny take on this.
Who wins this coin toss?
What exactly is the probability of Clinton winning all six tosses given that a fair coin is usedWhen a fair coin is used the probability of winning one toss is 1/2 or 50%.  The chance of winning two tosses is 1/4 or 25%.  In the case of 6 coin tosses, the chance of Clinton winning all 6 tosses is 1/64 or 1.6%.  This outcome is possible by pure chance but its likelihood is very small.

NPR has reported that there were in fact a dozen coin tosses and that Bernie Sanders won "a handful" of them according to an unnamed Democratic party official.  How many is a handful?  Can this number be independently verified?  Truth is a slippery thing indeed.  There is apparently this one video where Sander's did win a coin toss so he has won at least one toss.

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