Monday, November 12, 2018

More Accurate Political Polls

Pollster Who Got It Right in 2016 Does It Again
By Tom Bevan -- RCP Staff

November 10, 2018 -- Robert Cahaly, senior strategist for the Trafalgar Group, made a name for himself in 2016 by being the only pollster to correctly show Donald Trump with a lead in Michigan and Pennsylvania -- two key states he carried -- heading into Election Day. (He did not poll Wisconsin, another surprising win for Trump.) Cahaly also showed Trump ahead in North Carolina and Florida, both of which he won, securing his improbable 304-227 Electoral College victory over Hillary Clinton.

Cahaly managed to pick up support for Trump that all other pollsters missed by employing a unique method that sought to measure support from voters who'd been “inactive” in recent election cycles, as well as adding a question to his surveys designed to isolate the effect of social desirability bias among Trump voters – the concept that people won’t tell pollsters their true intentions for fear of being stigmatized or being politically incorrect.

After asking voters who they were supporting in 2016, the pollster followed up by asking them who they thought their neighbors were supporting, Trump or Clinton. Cahaly consistently found a high degree of variance between who respondents said they were voting for and who they thought their neighbors were voting for, suggesting there was in fact a “shy Trump effect” at play.

Two years later, Cahaly’s method once again proved solid. In one of the most polled races of the cycle, Trafalgar stood alone as the only polling firm to correctly show a Ron DeSantis gubernatorial victory in Florida – as well as Rick Scott winning the Senate race there. (Both narrow outcomes will likely result in recounts.)

Trafalgar also correctly predicted Senate outcomes in Missouri, Montana, North Dakota, Texas and West Virginia (as of this writing Arizona remains undecided), making it the most accurate pollster of the cycle among those firms that polled multiple Senate and governor races.

Even with Trump not technically on the ballot, Cahaly found social desirability bias playing a role. In the Florida and Georgia governor contests, some of that was attributable to race – often referred to as “the Bradley effect” – but Cahaly also found a “shy Trump” effect playing a role in places like the Arizona Senate race.

In the Georgia governor race, Cahaly’s results showed a big win for Republican Brian Kemp over Democrat Stacey Abrams. The final result, however, was a much closer Kemp victory. Cahaly gave credit to the Abrams campaign.

“They did a great job of registering voters late and bringing lots of new people into the process,” he told RealClearPolitics by phone on Thursday.

The same was true in Texas, Cahaly said, where Beto O’Rourke finished just 2.6 percentage points behind Ted Cruz.

Still, the pollster believes his method and methodology will be more valuable than ever as low voter response rates and social desirability bias continue to present challenges to all pollsters in the future.

“What few mistakes we made this time, we won’t make again,” he said.

Based on its record in 2016 and this year, Trafalgar is a polling firm to watch as Trump’s 2020 re-election bid heats up -- and an expected large field of Democrats jockey for the right to oppose him.

Tom Bevan is the co-founder and publisher of RealClearPolitics and the co-author of "Election 2012: A Time for Choosing." Email: tom@realclearpolitics.com, Twitter: @TomBevanRCP


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