The early days of a new presidential administration produce not just a blizzard of news but a blizzard of numbers. Pollsters of all stripes race to get and report Americans’ first impressions of their new president. But, frustratingly, those reports don’t always match up as precisely as the Type A among us might wish.
Take the past three weeks of polling on President Donald Trump. Depending on the poll, Trump’s approval rating between Feb. 5 and 13 could have been as high as 52% or as low as 39%. So which was it?
There are a number of possible reasons for polls arriving at different estimates – from the mode used to collect data to how people are selected for a survey – but here we’ll tackle one of the most basic: Did the poll include or exclude the 45% of adult Americans who didn’t cast a vote last November?
Typically, polls in the U.S. are designed to represent one of three populations. The broadest is the general population of all adults (GP). Surveys based only on adults who are registered to vote (RV) apply a narrower lens on the public. Narrower still is the filter applied with surveys that interview only registered voters who are deemed likely to vote (LV). Many pollsters might conduct surveys of all three, depending on where they find themselves in the election cycle.
The latest poll from RealClearPolitics.com:
| Thursday, February 16 |
| Race/Topic (Click to Sort) | Poll | Results | Spread |
|---|---|---|---|
| President Trump Job Approval | Pew Research | Approve 39, Disapprove 56 | Disapprove +17 |
| President Trump Job Approval | Rasmussen Reports | Approve 55, Disapprove 45 | Approve +10 |
| President Trump Job Approval | Gallup | Approve 40, Disapprove 54 | Disapprove +14 |
