‘Absolutely’ Wrong To Call Coakley-Brown Race A Statistical Tie

By Fred Thys
Jan 7, 2010, 4:55 PM
42 Comments

WBUR was wrong to declare a statistical tie between Senate candidates Martha Coakley and Scott Brown after seeing the results of a recent poll.

“One of the most misunderstood things in polling is the margin of sampling error,” said independent pollster Scott Rasmussen, who conducted the poll in question.

“Some people believe that when you say the sampling error is plus or minus 4.5 points, that any result is equally probable within that range”, Rasmussen said, “and so what they do, and apparently what you (WBUR) did is say: ‘OK, it could be 4.5 points better for the trailing candidate, 4.5 points worse for the leading candidate. You’ve got a tie, that makes it a statistical tie.’

“In reality, in polling theory, in statistical theory, when we release a result, the most likely outcome is exactly the result that we produce. If we were to do another survey, in theory, the most likely outcome is that we’d get the exact same number, but we report results with a margin of error that we say has a 95 percent level of confidence.

“That means that 19 times out of 20, the numbers will be within 4.5 points of what we are reporting. When you work your way through all the numbers, yes, it is theoretically possible that our poll could produce a result that would show the numbers identical, but it’s a pretty long shot.”

Rasmussen says “there is a meaningful difference” in the level of support for each candidate.

“If it’s 50 to 41, the support for Coakley could be, theoretically, from 45.5 to 55.5, whereas for Brown it could be from 36.5 up to 45.5, so those are two entirely different ranges.”

So what is a statistical tie?

“If we had found the candidates a single point apart,” Rasmussen said, “well, then that’s way too close to call, and I would say for all intents and purposes, that’s even.

“When you talk about the nine-point gap, we’re probably talking about a less-than-5 percent chance that these numbers would actually turn out to be equal. When you talk about a one-point distinction, it’s pretty much a tossup. If it was 50-49 in one direction, it could just as likely be be 50-49 in the other. There is no scenario within our margin of error, even the most extreme example, that would put Brown ahead in this case.”

Rasmussen said he is planning to poll this race again. He expects the results will be out next week.

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Hillary

Glad to see this — I heard that this morning and thought, “That can’t be right.”
krisd

Thank you Fred for posting the clarification.
http://cdevers.posterous.com/wburorg-news-absolutely-wrong-to-call-coakley Chris Devers

Also, it may have helped for someone at WBUR to have read at least some of fivethirtyeight.com’s analyses on Rasmussen’s surveys, e.g. Is Rasmussen Reports Biased? and Putting the [R] in [R]asmussen?, not to mention Politico’s “Low favorables: Democrats rip Rasmussen”.

While I’m perfectly willing to accept that Rasmussen’s average rightward skew is the result of statistical sloppiness rather than actual human political bias, it’s still a real, measurable effect, and if anything makes it even less likely that the Coakley-Brown race would be “tied” if there’s a 9-point spread with a 4.5-point margin of error.

Rasmussen puts the likelihood of that being a tie at “less-than-5 percent chance”. My hunch is that Nate Silver would put at a 5% chance that it’s really a 5% chance.
maureen in brockton

I urge all union employees to vote for Scott Brown, to stop not only this government takeover of healthcare, but to stop this totally incompetent president! He needed the union vote to get elected,so he pandered to their ranks. Now wee see in his new proposal, he will tax most of our healthcare plans at a rate of 40%.Something he was critical of in John McCain’s plan. At least McCain wanted to give a 5 thousand tax credit to shop for a plan. Time to send a free thinker to the senate.All union employees should Brown a donation. Coakley won’t even debate the man because she is an empty suit!!
matsuiny2004

If you care about healthcare reform and taking action on climate change vote for martha coakley.
matsuiny2004

Coakley is a supporter of SEIU and IBEW.
matsuiny2004

I am not even a person that think scott brown is all bad I just do not trust him.
Jon

It is really hard to understand how a veteran news organization like WBUR could end up playing amateur hour on a topic like this. Polling has been going on for decades and anyone who follows polling knows that the Rasmussen poll showed nothing close to a statistical tie. I sure hope someone in charge there looks more closely at how this could happen. This sort of reporting does not serve the public well.
Frank from Franklin

Citizens of Massachusetts, who cares about the polls and splitting hairs on who is winning! Vote for Scott Brown and give the Senate the filibuster it needs to stop the destruction of healthcare. These morons that believe it is “universal” and “you can keep your current plan”, forget to tell you they will tax it at 40%. What a bargain, we cover 3 million additional Americans and tax everyone else into the stone age. Do not put the political hack Martha Coakley in the Senate. Send a message. Vote Scott!
Matt

Vote for Scott Brown. Unlike Martha Coakley, he will serve this state just as the Kennedy family did for over half a century. Vote for liberty! Vote for Scott Brown!
chris

The democrats are looking quite petty over this. Stop embarrassing yourselves!
mommom

Conservatives are ok with voting for a man who posed nude for money? Seems like a small insight into his ethics to me.
angie

Brown is a corporate panderer, not to mention a right-wing extremist and a bigot. He will absolutely not be a supporter of the middle class and the issues important to middle class working people. Unions have endorsed Coakley for good reasons; they know Brown is and will continue to be in high level corporate pockets.

Brown has essentially no experience at doing anything. He ran a one issue campaign to get his current seat, playing on unjustified fears regarding same-sex marriage in true bigot fashion. He is slick and devious, and like the other guy with “good hair” (remember him?), will say anything to get elected.

Massachusetts deserves to be represented by a real progressive, someone with the courage to stand up against corporate greed, fight for the middle class, work towards equal rights for all Americans, and truly honor the memory of a man who dedicated his life to those principles.
Frank

I’m with Scott. He’ll treat terrorists as wartime enemies, not street criminals, and he’ll protect our wallets from higher taxes.
Kristyn

I find it hard to believe anyone could support Coakley. She kept an innocent man in jail to show she is tough on crime and then didn’t prosecute another hard enough after he raped a 23 month old with a curling iron because he was in a union supporting her (see Globe article from yesterday). How could anyone vote for this highly unethical person? Vote for Brown!
Joseph

I need to move to another country.
John

It would be nice to see some change in the political leadership of Massachusetts. The country wanted change with the Presidential election after only 8yrs of one party. When was the last non-Democrat senator from Massachusetts? It’s time to give some change in this state.
Dano

Of course we care about Health Care, but lets first do logical moves like tort reform and being able to buy across state lines before we totally ruin and spend ourselves into huge amounts of debt – give Scott Brown a chance, I like the idea he’s one of us, not a Washington type of politician. Help him.
Jane-Calvert Winkler-Kimble

I am reading the comments by other people and would like to point out something I have learned over a period of years through observation.

SPEAKING: how to tell a liberal. Liberals interrupt more often, speak faster, and speak more loudly.

WRITING: I have repeated noticed that liberals throw personal vulgar epithets at their opponents. Sort of childish isn’t it?

I could hardly believe what I was reading when I read angie’s comments. Tripe, worn-out, overworked phrases.
She is so out of touch with the majority of Americans, it is sad.
Big T

To Massachusetts Republicans:
Be careful what you wish for. The R party in Mass is very different than the rest of the country. I understand having republican governors balancing out the Dem legislature. But one more R vote in the Senate just empowers a party that right now is far, far to the right of the mainstream Mass republicans. If national dynamics were different, I might consider Brown, but not these days.
MuddyBuddy

How would Scott Brown serve as representative for Mass, when Mass is overwhelmingly Democratic, or moderate Republican. The US Senator has zero to doing with running the State and thus electing a Repbulican Senator will not change anything, other than the fact our state leadershipe will have more problems getting federal funds, but is very important representing Mass interests and views at the National Level. So electing a very right wing Republican would mean that the Citizens of Mass will not have their views represented at the National Level.
mike

angie get a grip.
And you have the audacity to call someone an extremist. Wow.
Howie Anderson

Polls are wrong most of the time. I would expect Coakly to lead in the P.R.O.M state.I look out my door and Russia. Coakly cheated on taxes, humm that sounds familiar. If you want a good lair vote for Coakly.A DINO and RINO running. Vote for Mafia or Military?
Gordon Row

I was relieved to see the ‘clarification’ provided by Scott Rasmussen regarding the “statistical tie”, but I am nevertheless dismayed that WBUR, of all places, ever made the egregious rashness of declaring it a statistical tie. (Full disclosure: I am supporting Coakley.) Beyond local elections, I am far more interested in mathematical literacy in America! Failing to understand the margin of error on statistics, and then using that ignorance to declare a juicy-newsy “tie” between candidates is just plain lame. Please send your political reporter to http://en.wikipedia.org/wiki/Margin_of_error or to any basic statistics text for some remedial education. You as reporters MUST be competent at that.
Tom

I agree with the comment of “Big T.” A vote for Brown is a vote for the national agenda of the GOP. This national agenda favors the red states like Texas, South Carolina and Utah. Don’t fall into that trap. Do what’s best for Massachusetts and vote for Coakley, the candidate who will have more clout for Massachusetts in these very difficult times.
paul

That “clout” won’t mean much in the future when the republicans are in the majority. Hopefully their national agenda will bring some spending accountability to Washington. Coakley, then will be useless.
Tom

Paul, we can see very easily what happens when the GOP has the majority in Washington. We got the Great Recession that started in 2007, we got torture, we got warrantless wiretaps, we got Iraq, we got corruption (Tom Delay, Scooter Libby, Jack Abramoff), higher unemployment, the largest national debt in history, a stock market crash, the bank bailouts (TARP), the auto bailouts. Please, look at the facts.
paul

Tom, the fact is the Democrats have controlled Congress for over three years and have been hugely involved in all the issues you just stated!
Tom

The bottom line on Brown is this: the center of the national GOP is somewhere between Texas and South Carolina. Voting for Brown is tantamount for voting for another voice for those states. He will be toeing the line for THAT agenda, not an agenda that will benefit Massachusetts and not an agenda that is consistent with the values of New England. If you are in favor of a Southern agenda, roughly that of what we got from George W. Bush, then by all means vote for Brown.
paul

Tom, I guess the discussion of facts is over with! As for having a Democrat voice in Congress, we still have Kerry whom has always been in the shadows of the late Ted Kennedy. Hopefully, he will step up and do some productive things for our state.

As for the “Southern agenda” you keep referring to, you give no specifics and are just basically labeling all people who live in the southern part of our country to having no values. Your tone is a little condescending.

As for Bush, who cares about him? You are showing your desperation with that comment. I thought this topic was about Congress.
http://wbur.org barb

Wow! I guess I am naive about the MA voter mindset. I do not have anything against Mr Brown, per se. However, with the very extreme right calling the shots for the Republican Party, would a moderate Republican from MA even have a voice? Just leave the seat vacant if you are going to elect moderate Republican. Of course maybe the majority of MA voters don’t want a moderate at all. Maybe a conservative senator is what we need, right? Be careful what you wish for…….
Tom

Paul, the facts about the GOP record during the Bush years speak for themselves. And regarding the national GOP agenda, let’s take just one example of how this might impact New England. In Texas, offshore drilling for oil produces vast riches for oil companies and refineries. It also creates lots of jobs for the people of Texas (and also lots of pollution in the Gulf of Mexico). Those industries lobby the GOP hard to expand offshore drilling whenever possible (remember “Drill Baby Drill” during the GOP convention in 2008?). However, drilling for oil off the coast of New England (and other coastal areas) just does not fit with New England values. Frankly, I don’t think Brown has the clout to stand up to such a powerful national GOP agenda backed by big oil, the banks and insurance companies.
paul

I think everyone is for less pollution and affordable energy. The trick is how can it be done? Just saying no to oil, natural gas, coal and nuclear energy gets the country no where. Those resources are enormous in this country but we would rather ignore it and buy oil from Mexico, Canada and the Middle East. Do you actually think the wind and sun can provide this country with all its energy needs? If so, that would be great.

You might want to look up the off-shore drilling bill from this past summer proposed by democrat Byron Dorgan and accepted by the Energy and Natural Resources Committee chaired by democrat Jeff Bingaman to allow leasing as close as 45 miles off Florida’s gulf shores and much closer in a gas-rich area called Destin Dome.

As for banks and insurance companies, the top two AIG recipients for 2008 campaign contributions were Chris Dodd and Barack Obama, whom both received over $100,000. In fact, – there’s that word again – eight of the top ten Congress recipients from AIG were democrats. Some of the political money was even given after they received the bailout that the democrat congress gave authorization to the Fed and Treasury.
http://www.BusinessLawPC.com EyeOnTheLaw

This office supports Massachusetts State Senator Scott Brown in his run for the United States Senate. Refreshingly, Senator Brown articulates his positions on even the most controversial issues openly and with no double speak. Do you support Brown or Coakley? We welcome your comments and votes: http://eyeonthelaw.blogspot.com/
Big T

Paul, under the last two two-term republican presidents, deficit spending grew at a greater rate in % and absolute dollars than under any democrat not named FDR.

The idea that Rs are fiscally conservative is, unfortunatly, just not true.

Under a republican Senate, you will see cuts in support for science and stem cell research, hurting our biotech & academic community, increase in weapons made in places like mississippi (thank you, sen cochran) killing raytheon & the shipyards, and a limit on progams like H1-B1. All of these would devastate the MA economy.
Don’t pretend one party spends less than another; worry about what they spend it on.
paul

If you want to talk yearly budget deficits, Obama’s deficit of 1.4 trillion for his first year is more than the eight years combined for Bush. Easily a new record. The national debt is over 12 trillion. In future federal budgets, the interest payments on that debt will become the largest item in the federal budget.
rondofan79

Thank you, WBUR, for correcting the record on this. You have restored my trust in your good name. Now I don’t have to ask for my pledge back!
http://text.donschaefer.net donS

Quote:
SPEAKING: how to tell a liberal. Liberals interrupt more often, speak faster, and speak more loudly.

WRITING: I have repeated noticed that liberals throw personal vulgar epithets at their opponents. Sort of childish isn’t it?
End quote

Oh, so Rush is a liberal? Hannity? Coulter? :>)

Who knew!!!
John

Ah Tom, if Brown were elected how would he be the voice of another state? (SC or TX).I’m sorry but when you are elected by a majority of the voters of MA that makes you their voice plain and simple.Obviously not your voice but clearly that of the majority.Sorry.
Charlene

Brown is rhetoric and hot air, a pretty boy in an empty suit. He mimics his party colleage Palin in his offensiveness, defensiveness, and emptiness. If you paid attention to his words, his message,his body language, and his marketing tactics used in the last debate, you should have read: EMPTY SUIT!

By the way, the seat you are running for Brown IS Kennedy’s seat since it was only due to death that it became available. The winner of this election assumes Kennedy seat…you claimed you didn’t know this either in your opening remarks in the last debate.
http://www.wbur.org Right of Rush

MA election is interesting to us in the South. You know we are clueless about the real world and politics…but understand this…we love our country and hate what the Dems have done to it. Look at the economy, car industry, banking, the national debt. Im sure you can make a great case for keeping the senate seat in Dem hands. Health care is hanging in the balance and so is your party. Just wait until the 2010 elections. On your side will be crying and nashing of teeth.
http://www.air-max-plus.com/ airmax

Very honored to see your blog.

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‘Absolutely’ Wrong To Call Coakley-Brown Race A Statistical Tie