Chart of the Day: The Bell Curve (of Hillary Clinton’s Polls)

Get your news from a source that’s not owned and controlled by oligarchs. Sign up for the free Mother Jones Daily.


As I mentioned last night, Hillary Clinton really is significantly ahead of Donald Trump in the national polls. She’s ahead by about four points, and that’s a pretty normal winning margin in a presidential election with no incumbent running. In the New York Times, Nate Cohn says the same thing but with a lovely little graphic to make his point:

Her lead is smaller than it was last month….But she retains an advantage — perhaps by 4 percentage points nationwide, and a similar margin in the battleground states that are likely to award the electoral votes needed to win the presidency. This straightforward story can get lost in the headlines, which tend to give the most attention to the most surprising results — whether it’s a predicted Clinton landslide or a narrow lead for Mr. Trump in key states.

The truth is probably somewhere between those extremes. Pollsters aren’t joking about the “margin of error”: the inevitable random variance in polls that exists simply by chance. If Mrs. Clinton leads by 4 points, you should expect polls that show her with a big lead or locked in a tight race, with others clustered around the average. That’s more or less what we saw this past week.

As Cohn says, individual polls are likely to fall on a bell curve. I’ve recreated his chart below, with actual recent polls in blue. As you can see, it’s all perfectly normal (pun intended).

What’s independent journalism worth to you?

Our news will always be free to read, watch, and listen to online. But what is its value?

Unbiased reporting on the issues that billionaire-owned newsrooms won’t touch. Fearless research into the dark corners of government and corporations. Ferociously fact-checked news that focuses on the facts, and the facts alone.

It IS free for you and every reader, viewer, and listener to utilize. But it’s not free for our team to make. So, what’s it worth to you? Let us know by making a donation: Make a one-time donation today to support this work. Or make a monthly sustaining donation to help us plan for the future.

Whatever you choose, know that you’re supporting more independent, investigative journalism in a time when we need it most.

What’s independent journalism worth to you?

Our news will always be free to read, watch, and listen to online. But what is its value?

Unbiased reporting on the issues that billionaire-owned newsrooms won’t touch. Fearless research into the dark corners of government and corporations. Ferociously fact-checked news that focuses on the facts, and the facts alone.

It IS free for you and every reader, viewer, and listener to utilize. But it’s not free for our team to make. So, what’s it worth to you? Let us know by making a donation: Make a one-time donation today to support this work. Or make a monthly sustaining donation to help us plan for the future.

Whatever you choose, know that you’re supporting more independent, investigative journalism in a time when we need it most.

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

INDEPENDENT. BECAUSE OF YOU.

Mother Jones has no billionaires calling the shots—just readers like you making fearless reporting possible

Donate