Results of a new poll conducted by WBUR/MassINC were distributed. The poll asked respondents from Massachusetts for whom they will vote: Democrat Hillary Clinton or Republican Donald Trump.
WBUR/MassINC poll results
The results show that 60.0% of participants are going to cast a ballot for former First Lady Hillary Clinton, while 31.0% are going to vote for businessman Donald Trump.
This poll was conducted from September 7 to September 10, among a random sample of 506 likely voters. The error margin is +/-4.4 percentage points. This means that the poll results for both candidates differ significantly.
Putting the results in context
As any other method, polls are subject to bias. In general, don't focus too much on the results of an individual poll. Rather than trusting the results from single polls, the recommended strategy consult combined polls or, even better, the combined PollyVote forecast that incorporates forecasts from different methods, each of which incorporates different data.
For the following analysis, we translate Trump's and Clinton's raw poll numbers into two-party vote shares. This procedure results in figures of 65.9% for Clinton and 34.1% for Trump.
Results vs. other polls
Looking at an average of Massachusetts polls, Clinton's two-party vote share is currently at 63.2%. This value is 2.7 percentage points lower than her corresponding numbers in the WBUR/MassINC poll. This difference is within the poll's sampling error, which means that the poll is not an outlier.
The poll in comparison with PollyVote's forecast
The current PollyVote expects Clinton to gain 63.9% of the two-party vote in Massachusetts. Hence, Polly's prediction is 2.0 points below her polling numbers. The PollyVote forecast is therefore in line with the poll's sampling error.