The polling folks are always terrified that they will repeat the mistake of 1948 \u2013 when the Chicago Tribune gloriously announced that Dewey had won the election. Then again CBS declared Gore the winner in 2000.<\/p>\n
The reason for the 1948 error was bad sampling – back then, many people did not have a telephone, and the polling was done by phone. The result was that richer people who were more likely to be Republican – were more likely to own a phone and were oversampled compared to the people who actually voted.<\/p>\n
In the first day of statistics class you are given a premise that the entire science of statistics is based on. When you have a “normal distribution”, you can… the problem is there are very few things that have a normal distribution.<\/p>\n
Let’s start with a simple case – if you know that 52% of likely voters are women, but your sample winds up with 56% women, you have a sampling error. If women and men vote similarly, no big deal – but if not, you need to figure out why women are more likely to answer the poll. One might thank women when they reach 52% and hang up or ask if there is a male in the household to improve the sample. If you are lazy, you just “weight” each vote higher or lower to fix up the faulty sample.<\/p>\n
Rush framed the issue today much better than the foaming at the mouth Alex Jones. The problem is all of the polls are weighting based on what people state as their party affiliation. In North Carolina, Barack Obama got 48% of the vote and Romney got 50%. If you reach 1,000 people, some portion will say they are Republicans and some will say Democrats, and some will claim to be Independents – but they are lying. They are telling you which party they intend to vote for, not which party they belong to. They all will say they are going to vote, but 1\/3 won’t actually vote.<\/p>\n
So weighting the sample based on what people as a group did 4 years ago is a really bad idea. Get the age, sex, rural vs urban, race, income to a reasonable representative sample and don’t weight by party. The data coming in suggests that many blacks are not going to vote. You can’t assume if a certain portion of the NC population is black and voted for Barack Obama that they’ll turn out in the same numbers to vote for Hillary.<\/p>\n","protected":false},"excerpt":{"rendered":"
The polling folks are always terrified that they will repeat the mistake of 1948 \u2013 when the Chicago Tribune gloriously announced that Dewey had won the election. Then again CBS declared Gore the winner in 2000. The reason for the … Continue reading