more phone calls or texts recently from numbers, you don't recognize.

>> There's a chance it's coming from an election polling center.

Recent polls, the presidential candidates, Kamala Harris and Donald Trump are neck and neck.

But what are actually tell us and what impact they have?

Joining us now is Eric Nisbett, professor of policy analysis and communication at Northwestern University.

Eric, Welcome back.

Thanks for joining us.

You're welcome.

Thank you.

so of course, there are a lot of polls out there.

How do you distinguish from one a reliable poll from an unreliable poll?

>> Right.

There are many different polls and posters out there.

And I think one of the key sort of shortcuts is you're recognize who's doing the poll.

Is it coming from a major media outlet?

Washington Post ABC News, New York Times, for example, what your local major newspaper, those polls tend to have higher quality and you can't pretty.

You are confidence in their methodology is representing voters opinions accurately.

>> Now over the weekend, new poll numbers about the state of Iowa came out now.

This is a state that former President Donald Trump carried the last 2 elections.

This time this poll showing that Vice President Kamala Harris is leading by about 3 points with 47% of polar polls.

People being pulled their surveyed saying they'd vote for her.

What are the latest polling numbers telling us?

>> Well, that goes quite a bit of a shocker and how you know, Trump won Iowa by about 8 points in 2020 and other polls have him up about the about the same amount.

If that well is accurate.

And the reason that the poster said that there is such a shift my harris's because older white women were breaking for her.

Late voters are voting for her, possibly around issues of abortion and other issues.

Important to them on The question is whether that is an outlier or possibly tracking a larger trend nationwide in terms of the gender split in this vote overall, we should be really looking.

I not seen as a battleground state, really, want to focus on where what polls are probably most predictive of who will win the election.

It's those battleground states, Pennsylvania, Michigan, Wisconsin, especially should be looking at.

>> What impact of polls have on voters?

you know, can it make voters more complacent or energize them?

>> Little bit of both, depending on your point of view, if you're candidate is way up in the polls, maybe you're apathetic.

You're not gonna spend time to stand in line and vote.

You know, voting takes time and effort and you think of your candidates going anyways.

Why do you spend that time and effort?

That's why often campaigns sort of did a do rely on polls that show the way had those caution, their voters that this is not very accurate and you get out the vote at the same time if a vote, those your candidate is behind, maybe will energize.

make sure you get to the vote and then heard and try to make up that deficit.

So, you know, there's sort of a double edged sword how close might impact voters.

>> The polls in 2016 poor certainly cast a lot of doubt on the validity of polls.

But national polls tell the whole picture.

>> They especially because we have that tomorrow college and unfortunately United States, the popular vote doesn't determine who's president.

Now, there is sort public Holland tunnel, college bias that Democratic candidate needs to win about my 3 or 4 points nationally in the popular vote to overcome the bias against them in the Electoral College.

In terms of our sort of red and blue divisions right now, my Harris's polling below that at least if the polls are accurate, more in the one to 2 range and that's what it comes down to the battleground states.

That's why a lot of holes are.

48 48 50, 50 48 49.

And while the forecast it's a coin flip because it's so close both nationally as well in battlegrounds.

>> Eric, How's polling changed over the years?

>> There's diversity in polling methods, you know, online via text telephone and posters are using combination of methods.

it's not that poster only use of the telephone.

Now they try to contact people by mail, telephone hotline to reach people because it's recently more possibly more expensive to reach people and people are not actually answering polls.

You know, the gold standard.

Those still is the telephone pole.

It's a probability sample to make sure that everyone has equal chance of being included in the poll.

And those are the polls that are conducted by, for example, you know, New York Times or Washington Post, those polls are more expensive.

They take longer to do.

But even the confidence of those polls and most accurate, was representing voters, opinions.

>> And explain margin of error because we often see a lot of polls you know, there's 3 three-point margin of error.

Explain that for us and why it matters.

Please.

>> Margin error really tells you know how much the results they give.

You can actually differ from the reality.

So if I say that Kamala Harris is at 48% and Trump is a 48%, I have a margin of error of 4%.

That means you know, to be anything from 44 to 52 within that range, right?

So there's a wide window.

So the larger the margin of error, the larger the window, the true results could actually be.

And so that's why you want a little margin Erica's.

You have more confidence that the numbers that you get from the accurately represent voters.

>> And lastly, you know who to say pays attention to these polls, as you know, is the voters and campaigns the most.

>> a little bit of both campaigns about internal polls that never see the light of day and they usually trust their internal polls more than the public wants, though.

They have to respond to them in their communication messages.

They might actually use them for fundraising.

Right is of a poll shows a candidate behind you will guarantee said, you know, I've Campa highest Donald to give you some money on your taxes, using the as fodder terms of voter.

I think voters pay attention but really should be attention to the big picture chair pay attention to any one single poll.

Look at polling averages.

Look at polling trends rely on analysis from some of the experts at the major media networks that can give the polls in context because that's really should be paying attention to.

>> Right.

A lot voters think about heading into tomorrow if