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FiveThirtyEight

SENATEUPDATEColorado is a tipping point state in presidential elections — lately, it’s been the tipping point state. Arrange all the states by President Obama’s margin of victory in 2012, starting with his biggest wins, and add up each state’s electoral votes. The state that gets you to 270 is the tipping point state. In 2012 and 2008, that was Colorado.

Colorado’s place at the center of the political universe seems to be secure this year. The Senate race between Democratic Sen. Mark Udall and Republican Cory Gardner has been one of the most competitive for most of campaign season.

That’s why the strength of Gardner in recent polls has been so important in our Senate forecast, which currently gives Republicans a 66 percent of securing a majority. Gardner’s chance of winning has risen to 80 percent. He has led in all but one of 15 nonpartisan sponsored surveys released since mid-September, and by an average of 3.4 percentage points. That includes a newly released Ipsos poll that has Gardner ahead 47 percent to 45 percent, and a new Suffolk University poll that found Gardner up 46 percent to 39 percent. Gardner was only ahead by 1 percentage point in the previous Suffolk survey.

Yet we’re beginning to hear arguments not to trust the polls in Colorado. Skeptics point to polls there in 2010 and 2012 that underestimated Democratic strength. Others argue that the polls aren’t including enough Latinos, and that there’s too many white respondents. Or that the Latino vote is too Republican-leaning. Or that maybe Colorado’s vote-by-mail system will complicate things, making it harder to know who will vote this year.

Pay no attention to those public polls. Instead, Democrats are pushing two recent surveys by the well-respected Democratic pollsters Joel Benenson and Mark Mellman, both showing Udall leading by 3 percentage points.

I don’t put much stock in any of these arguments. Let’s take them one at a time:

It’s true that polling in Colorado has overestimated GOP support. The FiveThirtyEight projections in the 2010 Senate race and 2012 presidential race, mostly based on the polls, were off toward the Democrat by 2.7 and 2.9 percentage points, respectively.

But Gardner’s lead is nearing a point at which he could afford a polling error of that magnitude. He’s up by 2.4 percentage points in our latest projection. Udall would need every bit of those past errors to pull out the victory.

You’d also have to think the mistakes pollsters made in the past will happen again this year. But pollsters adjust their methodologies. Furthermore, two elections in a row doesn’t mean the polls “always” underestimate the Democratic candidate in Colorado. In Udall’s last campaign, in 2008, he was projected to win by 11.1 percentage points by FiveThirtyEight. He won by 10.3 points. In other words, the FiveThirtyEight estimate — again, based mostly on the polls — slightly overestimated Democratic strength.

Second, there’s isn’t much evidence public pollsters are overestimating the share of Latinos will make up of voters. The recent Benenson and Mellman surveys projected the electorate to be 84 percent white and 9 percent Latino, and 79 percent white and 9 percent Latino, respectively.

What have public pollsters found? The past five polls released in Colorado to list demographic breakdowns have used samples, on average, 79.7 percent white and 11.3 percent Latino. In other words, the public polls are less white and more Latino than the two recent Democratic-leaning surveys. These five public polls found Gardner ahead by an average of 4.4 percentage points.

So, we don’t have any compelling reason so thing the public polls are underestimating Latino turnout, but maybe they’re reaching disproportionately Republican-leaning Latinos?

Not really. The Benenson poll, which showed Udall up 3 percentage points overall and released a breakdown of the vote by race, had Udall winning by 22 percentage points among Latinos. The past five public polls with a Latino crosstab found Udall leading by 28 percentage points among Latinos, on average. The Suffolk poll released Wednesday had Udall winning Latinos by 73 percentage points.

Picking apart a poll’s subsamples, which have big margins of sampling error, is usually a waste of time. But for what it’s worth, these public polls have had Latino subsamples more Democratic-leaning than the left-leaning polls.

The real reason the public polls differ from the Benenson and Mellman surveys is because the public polls have Gardner doing better among white voters. Gardner leads among whites in those five public polls by 10.6 percentage points, on average. In the Benenson survey, Gardner and Udall were tied among white voters. Whites make up most of the electorate, and so that lead is worth 8.4 percentage points in the overall sample — pretty much the entire difference between the public polls and the Benenson survey.

Finally, it’s possible that all-mail voting will throw off the pollsters, but there isn’t any evidence it will. Oregon has had all-mail voting since 2000, and Josh Katz of The New York Times has found it had the seventh-lowest error rate in Senate polling out of the 36 states he studied. Washington switched to all-mail voting for the 2012 election, and the polling average in the 2012 Senate race was off by 0.5 percentage points.

Pollsters haven’t had problems with vote-by-mail states.

The FiveThirtyEight forecast projects Gardner as an 80 percent favorite. The polls aren’t too far off from our model’s “fundamentals” projection, which accounts for the state’s partisan history, the national political environment, candidate quality and candidate fundraising. Gardner leads in our fundamentals projection by 0.5 percentage points.

The polls and the fundamentals tell the same basic story: An unpopular incumbent is losing in a purple state against a decent candidate in a slightly Republican-leaning year. That’s a pretty believable story.

Check out FiveThirtyEight’s latest Senate forecast.

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A study released this week finding that three Ebola-infected air travelers could be leaving the three affected West African countries each month based its estimate on some big assumptions.

The researchers assumed that people infected with Ebola would take commercial flights at the same rate as everyone else in their countries. They assumed the official counts of the people infected were accurate. And they assumed those counts would remain static.

Tweak those assumptions, as the researchers did in the appendix to their Lancet article, and the numbers change significantly.

Take the case of Guinea. The researchers estimated it would take, on average, 2.7 months for one Ebola-infected person to leave the country — if air travel were at the levels it was at the end of last year. Factor in the restrictions to air travel because of Ebola fears, and it would take eight months. In other words, there would be about a 50 percent chance of someone infected with Ebola flying out of Guinea between the start of September and the end of the year.

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But according to the appendix, if the real case burden is 10 times the reported level, and air travel isn’t restricted, then about 15 people would fly out during that period. Switch instead to an exponential growth rate in number of Ebola cases, and 45 infected people would leave the country by plane between September and December.

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One assumption the researchers didn’t change in the appendix is that all people in each country have an equal chance of flying — whether or not they have Ebola. “I don’t know how realistic that is,” Andreas Handel, an assistant professor in the department of epidemiology and biostatistics at the University of Georgia’s College of Public Health, said in an email. He pointed out that the ability to fly internationally is likely to be correlated with better sanitation and access to health services. “All of these uncertainties make me very hesitant to attach too much meaning to any specific number,” Handel said.

Kamran Khan, lead author of the Lancet study, said he and his colleagues had no data to assume otherwise. “We highlight this as an important limitation in our manuscript,” Khan, an infectious diseases specialist at the University of Toronto, said in an email. He and his co-authors point out in the paper that visiting health-care workers have both a higher chance of infection and of being able to fly internationally than do most residents of Guinea, Liberia and Sierra Leone.

To make their estimates, the Lancet authors combined flight data from the International Air Transport Association, World Health Organization estimates of Ebola cases, and World Bank population data.

Although the estimate of three infected travelers per month is what made headlines, the paper also includes other interesting data on Ebola and air travel, such as the projected share of traveler volume from the three affected countries to various worldwide destinations (2 percent to the U.S.).

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And the report isn’t alone in making big assumptions to project the spread of the Ebola epidemic. Researchers from the U.S. Centers for Disease Control and Prevention, for instance, made many assumptions in projecting 1.4 million worldwide Ebola cases by late January. Calculations during the outbreak, with limited and incomplete data, will necessarily be approximations.

Whether the true number is three infected air travelers per month or not, Khan said, a travel ban isn’t a solution. “The most proactive and preventative way to decrease the risk of international spread would be to decrease the number of new infections in West Africa,” he said. “Travel bans wouldn’t address the root cause of the problem and could compromise the international community’s ability to manage the outbreak in West Africa, which ultimately should be the top priority.” Exit screening travelers for Ebola symptoms is more sensible, he and his co-authors wrote in the paper.

The paper’s estimates also don’t translate into a significant chance of catching Ebola while flying, even at the upper end of the range, according to other researchers. “The chance of sitting next to an infected person would be greatest on a flight originating in Liberia, Sierra Leone and Guinea, but even there it would be very unlikely,” Benjamin Neuman, a virologist at the University of Reading in Britain, said in an email.

“I didn’t try to crunch the numbers, but I would venture a guess that currently the overall risk of getting and dying from Influenza while on a flight from NYC to London are probably higher than getting and dying from Ebola during such a flight,” Handel said. “That could of course change if things get worse and we don’t get the situation under control soon.”

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Sohan Murthy at the LinkedIn blog published a map Wednesday that shows which skills and jobs are most disproportionately represented in American cities based on data from LinkedIn members.

Here’s LinkedIn’s map:

The map doesn’t show the most common job in each city; that’s another metric and would probably make for a pretty boring map, all things considered, because the plurality of Americans work in sales. Instead, it shows which jobs are observed at a disproportional rate in different metropolitan areas among LinkedIn members (which may not represent the general public).

Murthy points out a few things about the map: You can see America’s major energy hubs along the Gulf of Mexico and around Bismarck, North Dakota. And many cities fit their stereotype: D.C. with its public policy obsession, New York with its finance types, and Nashville, Tennessee, with the music business.

But it’s also fun to compare the prevalence of jobs within cities. “Mining and commodities” is bigger in Las Vegas than “travel” or “restaurant and catering,” which leads me to think that what happens in Vegas doesn’t stay in Vegas — it’s exported to industrial consumers of raw materials. I thought writing and publishing would be more disproportionately popular in New York than, say, general finance, but that’s just the bubble I’m in.

The map also happens to pick out a few other unexpected but sensible findings. Look at the gray dots, and you see a map of major U.S. military installations. It wasn’t shocking to see Seattle’s a hub for tech, but I was surprised that Boise, Idaho, was. As it tuns out, some of the largest employers in the Boise area are circuit designers.

There’s also a ton of data from European cities. Check out the whole treatment by Murthy on LinkedIn.

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The Denver Broncos, who moved into the top slot in our Elo ratings last week, widened their advantage over the rest of the league in Week 7. Denver looked dominant in beating the San Francisco 49ers, who had been the No. 3 Elo team. The No. 2 Seattle Seahawks lost — greatly imperiling their playoff chances — as did the No. 5 San Diego Shargers. The No. 4 team, the New England Patriots, barely won against an awful opponent, the New York Jets.

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So, it’s time to pose the question Aaron Schatz asked at Football Outsiders. Is this Denver team merely the best in the league — or one of the best teams ever?

The Broncos’ Elo rating is 1683, which translates to being favored by a touchdown in a neutral-site game against an average opponent. It’s also a fairly typical rating for the best team in the league at this point in the season. On average since 1970, the highest-rated team through Week 7 had an Elo rating of 1686, almost exactly matching Denver’s this year.

Let’s pick some nits with the Broncos: They’ve lost once this year. They had a bye week. They fizzled in the second half against the Indianapolis Colts. And they were crushed in last year’s Super Bowl.

Is this unfair? Except perhaps for the Super Bowl part, of course it is. Denver’s loss came on the road at Seattle and may have literally been the result of a coin flip. Beating Indianapolis by any margin looks more impressive given how well the Colts have played since. It’s not the Broncos’ fault that the schedulers gave them an early-season bye (and thereby one less opportunity to improve their Elo rating). More sophisticated statistical treatments — from Football Outsiders’ DVOA (Defense-adjusted Value Over Average) to Benjamin Morris’s assessment of Peyton Manning’s clutchness — tend to have a higher opinion of the Broncos than Elo does.

But if we’re judging whether the Broncos are a historically great team, we have the right — nay, the duty — to be very, very picky.

This is not just an academic question. In the table below, I’ve taken the teams that had the highest Elo rating through Week 7 in each season since 1970. Eleven of the 25 teams that rated higher than the Broncos — or 44 percent — would go on to win the Super Bowl. But just two of the 19 (11 percent) that rated below the Broncos did.

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A lot of this is because even small advantages can compound over time. It’s not as though we can say with all that much confidence whether this year’s Broncos are better than, say, the 1998 edition of the team under John Elway. (Elo would have the 1998 Broncos favored, but by only 1.5 points). But a team that’s ever-so-slightly better is more likely to make the playoffs as a division champion rather than a wild card, more likely to have playoff games at home and to get a first-round bye, and more likely to win those playoff games once they occur. A team that’s a 70 percent favorite in each playoff game, and that needs to win three games to win the Super Bowl because it gets a bye, has a 34 percent chance of winning a championship. A team that’s a 60 percent favorite and that has to win four times has just a 13 percent chance.

Elo puts the Broncos’ chances of winning the Super Bowl at 18 percent, somewhere between the two groups. Their Thursday-night home game against San Diego will be highly informative. A win for Denver would put it in a dominant position in the AFC West — it’d be a game-and-a-half ahead of the Chargers and at least two games ahead of the Kansas City Chiefs (with a tiebreaker advantage against each division rival). A loss to the Chargers would instead place Denver half a game behind San Diego with a tiebreaker disadvantage (and with the remaining game between the teams to be played in San Diego).

The Broncos will probably make the playoffs as a wild card even if they lose their division, but the Super Bowl is much harder to win under those circumstances. The Broncos would have to play an extra game, and they’d have to play on the road. In our simulations, the Broncos won the Super Bowl 23 percent of the time as division champs but just 4 percent of the time as a wild card team. There’s not only playoff leverage riding on this game; there’s a lot of Super Bowl leverage at stake.

Here are the current playoff odds for the other NFL teams:

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The Colts, who were briefly underdogs to make the playoffs after starting off their year 0-2 (Seahawks fans can take solace in that), are now 95 percent favorites to do so after having won every game since. Some of this is because the Colts are very good, but just as important is their extraordinarily weak division. The Houston Texans project to a record of 7-9, the Tennessee Titans 6-10, and the Jacksonville Jaguars (despite finally winning last week) 4-12. In our simulations, the Colts won the AFC South 82 percent of the time they finished with a 9-7 record and 62 percent of the time they went 8-8. Even a 7-9 record would often be enough to get them in. Andrew Luck is both lucky and good.

Otherwise, the AFC playoff chase is more scrambled than last week. The Cincinnati Bengals are winless in their past three games (they managed a tie against the Carolina Panthers) and down to a 54 percent chance of making the playoffs, in danger of being lapped by Kansas City (41 percent) and the Pittsburgh Steelers (33 percent). Their matchup this week, at home against the division rival Baltimore Ravens, is another high-stakes game.

The NFC, almost inevitably, will feature a ferocious battle for the wild card positions. Dallas, Philadelphia, Green Bay, Detroit, Arizona, San Francisco and Seattle all have somewhere between a 22 and 32 percent chance of winning a wild card. Three of those teams (barring a miraculous run by a team like the Chicago Bears) will win their divisions, but that leaves four teams fighting for two slots.

The Arizona Cardinals, incidentally, have a chance to become the first team to play a Super Bowl in its home stadium. Although Arizona is probably weaker than either San Francisco or Seattle, it has a leg up in the NFC West by virtue of its 5-1 start. Elo gives the Cardinals a 15 percent chance of making the Super Bowl and an 8 percent chance of winning it.

Elo point spreads

Record against point spread: 49-50-3 (8-7 in Week 7)

Straight-up record: 74-31-1 (10-5 in Week 7)

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Even if we thought you should bet based on these odds — and we don’t — it wouldn’t be in cases where bookmakers have a team as a 2.5-point favorite and Elo has the same team favored by, say, two points. There are a lot of games like that this week and fewer differences between Vegas and Elo than in past weeks. The biggest split of the week is in an unwatchable game: Elo has the Titans favored by three points at home against Houston, while Vegas has the Texans as one-point favorites.

The Washington Redskins are also a perpetual punching bag for Elo, and the system would have you take the Dallas Cowboys against them (even as 9.5-point favorites, as Vegas has the Cowboys). As Washington was on the verge of losing to the Titans last week — it pulled the game out but didn’t cover the point spread — The Wall Street Journal’s Neil King tweeted that Washington was struggling to beat “the third worst team in the league,” presumably referring to Tennessee. Actually, Elo has Washington rated as the third-worst team! Washington went 11-5 against the point spread in 2012 and perhaps is still getting too much credit for it; it’s 7-16 against the spread since then. The team’s straight-up record, 5-18, is even worse.

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SENATEUPDATERepublicans are 66 percent favorites to win a Senate majority, according to the latest FiveThirtyEight Senate forecast. New polls confirmed GOP advantages in Arkansas and Colorado, and a generic ballot survey from AP-GfK found Republicans up 8 percentage points — an unusually large lead.

But — as I’ve written before — there’s a good chance we won’t know who controls the next Senate when the sun rises on Nov. 5. We may have to wait, as we did for the 2000 presidential election. But not because of hanging chads and the Supreme Court. With a possible runoff in Georgia, a probable runoff in Louisiana and the specter of independent Greg Orman in Kansas taking his sweet old time deciding whom to caucus with — not to mention potential recounts — the 2014 midterms may remain unresolved until you’re shopping for Christmas presents (or even making New Year’s resolutions).

So we’re introducing a new metric as we enter the campaign’s final stretch: The probability that Republicans or Democrats will have a majority of Senate seats on or near Nov. 4. We’ll call this a regulation-time win.

Here’s how it works. In each simulation, the FiveThirtyEight model counts up all the seats except:

  • Louisiana, where a runoff is very likely;
  • Georgia, if neither candidate gets above 50 percent (the threshold to avoid a runoff);
  • Any independent win (Kansas or South Dakota);
  • Any race with a margin of victory within 0.5 percentage points (which could necessitate a recount).

If the GOP has at least 51 seats without these cases, that’s a regulation-time win. If Democrats have at least 50 seats without these cases (with Vice President Joe Biden breaking the tie in the Senate), that’s a regulation-time win.

As of Tuesday’s model run, there is a 53 percent chance we’ll be able to project Senate control near Nov. 4; 47 percent of the time, the midterms go to overtime. It’s basically a coin flip.

Republicans have a 38 percent chance of securing the majority near Nov. 4. Democrats have only a 15 percent chance.

It’s possible this calculation underestimates the chances we’ll know the winner within a day or two of Election Day. In 2008, it took two weeks for Sen. Mark Begich to be declared the winner in Alaska. His margin of victory was small but not that close. He won by just over 1 percentage point. It’s not hard to imagine that even a 2 percentage point or 3 percentage point victory could take a while to finalize in Alaska. Republican Dan Sullivan is projected to win Alaska by about 4 percentage points.

If we assume we won’t know Alaska right away, the chance of a regulation-time win for either party falls to 36 percent — 64 percent of the time, we’re left waiting (without a call in Alaska, the GOP wins in regulation 24 percent of the time, and the Democrats win and avoid overtime in 12 percent of simulations).

The GOP’s most likely path to regulation-time victory includes sweeping Alaska, Arkansas, Montana, South Dakota and West Virginia. FiveThirtyEight currently has Republicans with at least a 75 percent chance of winning in each of these states.

The GOP would also need to win three of the following five states: Colorado, Georgia, Iowa, Kansas and Kentucky. FiveThirtyEight has Republicans as 74 percent favorites in Colorado, 65 percent in Iowa and 78 percent in Kentucky. Results in these states are correlated, but not enough to make Republicans favorites to sweep all three. FiveThirtyEight also forecasts that Georgia is more likely than not to go to a runoff, and that Orman has a 54 percent chance of winning in Kansas.

Democrats have a narrow path to regulation-time victory. That’s because Republicans have a good shot at sweeping Alaska, Arkansas, Montana, South Dakota and West Virginia. For a regulation-time win, Democrats would need to win one of those states, or be forced to sweep the remaining battleground races. They would need to win three of the following four contests: Colorado, Georgia (with a majority), Iowa and Kentucky. Democrats are favored to win in zero of these states. (And this scenario gives them New Hampshire and North Carolina, neither of which is a sure thing.)

Fortunately for political reporters who have scheduled vacations in November or December, it’s still more likely than not that someone will win in regulation time — but just barely.

Check out FiveThirtyEight’s latest Senate forecast.

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Christophe de Margerie, chief executive of French oil giant Total, was killed Monday night when his private jet hit a snowplow while taking off in Moscow. News reports say the plow driver was drunk. Three crew members also died in the accident.

De Margerie was a colorful figure — his impressive mustache made him unmistakable at industry events — and fond remembrances poured in from both business and political leaders when news of the tragedy became public. He was remembered for being forthright and accessible, not common qualities in an industry where CEOs are often guarded by a phalanx of public-relations staffers.

De Margerie isn’t the first prominent executive to die aboard a private jet, though such incidents are rare. Earlier this year, Lewis Katz, the co-owner of the Philadelphia Inquirer, died when his Gulfstream IV exploded on the runway outside of Boston. Others, such as Micron CEO Steve Appleton, have been killed while piloting their own planes. And of course, there’s a long list of celebrities, from former Alaska Sen. Ted Stevens to singer John Denver, who have died in plane crashes. Most, though not all, have been aboard private aircraft.

That made me wonder whether corporate jets are riskier than commercial airliners. Big companies routinely pay for their top executives to fly private, and many actually require it, even for personal travel. The board of directors at Exxon Mobil, for example, “requires the Chairman and CEO to use Company aircraft for both business and personal travel,” according to the company’s latest proxy statement. (I couldn’t immediately determine whether Total has a similar policy.)

The National Transportation Safety Board collects data on aircraft safety in the United States. At first glance, it looks like it’s much safer to fly commercial: “General aviation” — the umbrella term for noncommercial flights — recorded 70 accidents and 12 fatal accidents per 1 million flight hours in 2012. Commercial airlines had just 1.5 accidents per 1 million hours, and no fatalities.

But general aviation is a broad category that lumps together professionally operated corporate jets like de Margerie’s and tiny two-seaters flown mostly by amateurs (some of these planes, such as Appleton’s and Denver’s, are homemade or have experimental designs). Personal planes are by far the most dangerous, with an accident rate of 120 per 1 million hours. Corporate jets, by contrast, rival commercial aircraft in terms of safety: They had 4.7 accidents and 0.8 fatal accidents per 1 million flight hours in 2012. Moreover, four of the 11 corporate accidents in 2012 involved helicopters, not planes.

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In other words, corporate jets aren’t necessarily any safer than commercial flights, but they aren’t much more dangerous, either. As Slate noted in 2008, executives have other reasons for flying private. Companies, including Exxon, usually cite security, but private jets also offer other advantages: flexible schedules, privacy and a better environment for getting work done. Of course, they’re also a nice executive perk — one not all companies decide is worth the money. Microsoft, for one, is famously stingy on business travel: Bill Gates flew coach for much of his time as Microsoft’s chief executive, though he later bought his own plane.

De Margerie, 63, is survived by his wife and three children.

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inthepapers

Every Monday, the National Bureau of Economic Research, a nonprofit organization made up of some of North America’s most respected economists, releases its latest batch of working papers. The papers aren’t peer-reviewed, so their conclusions are preliminary (and occasionally flat-out wrong). But they offer an early peek into some of the research that will shape economic thinking in the years ahead. Here are a few of this week’s most interesting papers:


 

Title: “Foreclosure, Vacancy and Crime”

Authors: Lin Cui, Randall Walsh

What they found: In Pittsburgh, foreclosures alone did not influence crime, but when a foreclosed home was abandoned, violent crime rates increased in the surrounding neighborhood.

Why it matters: The conventional wisdom is that foreclosures lead to crime, but this paper shows that the relationship is more complex. When a house goes into foreclosure, it doesn’t necessarily result in higher crime rates in the surrounding area, according to the research. The real trigger is when the residents vacate the foreclosed home. Interestingly, the researchers found that only violent crime in Pittsburgh increased; property crime was unaffected.

Key quote: “Using detailed data on addresses and dates of foreclosures and crime, we estimate that, on average, violent crimes within 250 feet of foreclosed homes increases by roughly 19% once the foreclosed home becomes vacant, compared to crimes in areas between 250 and 353 feet away. Foreclosure alone is found to have no effect on violent crime.”

Data they used: Crime data from the Pittsburgh police department; foreclosure filings data from City of Pittsburgh court records; data from Allegheny County on housing transactions and characteristics.


 

Title: “Second Trimester Sunlight and Asthma: Evidence from Two Independent Studies”

Authors: Nils Wernerfelt, David Slusky, Richard Zeckhauser

What they found: A pregnant woman’s low level of vitamin D during the second trimester increases the odds of her child later becoming asthmatic.

Why it matters: Asthma afflicts over 300 million people worldwide, and 1-in-12 Americans. Yet the causes of asthma remain poorly understood. These researchers believe they’ve found one significant cause: lack of sunlight, which is a major source of vitamin D. Controlling for time of year and location, they found that children were admitted to the emergency room for asthma attacks 20 percent less often when their mother had twice as much sunlight exposure during her second trimester.

Key quote: “Our results suggest low levels of maternal vitamin D during pregnancy may be more harmful than previously thought. As mentioned earlier, vitamin D deficiency and insufficiency are extremely widespread, with multiple studies of pregnant women documenting overall rates in excess of 80% (Bodnar et al., 2007; Holmes et al., 2009; Johnson et al., 2011). Hence, our results suggest that if we could raise vitamin D levels in these women, the savings in terms of both future quality of life and healthcare costs could be substantial.”

Data they used: U.S. county-level data on more than 2.1 million births.


 

Title: “A Tale of Repetition: Lessons from Florida Restaurant Inspections”

Authors: Ginger Zhe Jin, Jungmin Lee

What they found: First-time restaurant hygiene inspectors report about 15 percent more violations than repeat inspectors.

Why it matters: Keeping restaurants clean is a duty of public health regulators, but it comes with thorny game theory problems. The thinking has been if you inspect restaurants on multiple occasions, and randomly, the restaurants won’t be able to game the system. But it matters who the inspectors are. If the same person inspects the restaurant on multiple occasions, then they report fewer violations — specifically between 1 and 2 percent fewer violations, as this paper reports. But if the inspections are conducted by different people, the number of violations increased about 13 and 18 percent.

Key quote: “We use restaurant hygiene inspections as an example to show that inspector assignment and repetition can have significant impact on inspection outcomes. In particular, we find that new inspectors report 12.7-17.5% more violations than the second visit of a repeat inspector, and this effect is more pronounced if the previous inspector has had a longer relationship with the restaurant. The difference between new and repeat inspectors is attributed to two factors: (1) new inspectors tend to have fresher eyes in their first visit of a restaurant; and (2) inspectors differ greatly in stringency and taste, such inspector heterogeneity motivates restaurants to adjust their compliance effort according to the criteria of their previous inspectors. Both factors are found to be important in our data.”

Data they used: Restaurant hygiene inspections in Florida from July 2003 and March 2010.

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Politico reported on Monday that Democrats are in danger in November’s midterm elections — because of Ebola. According to a Politico poll, Republican-leaning voters have less confidence than Democratic-leaning voters in the government’s response to the Ebola crisis.

Um.

I have little doubt about the poll’s finding, but Politico’s interpretation is backwards. Some Americans might vote differently because of the Ebola outbreak and the government’s response to it, but the fact that Republican voters distrust the federal government isn’t evidence of that. Ebola isn’t making people more likely to vote Republican. Rather, Republicans are more likely to have less confidence in the government while a Democrat occupies the White House.

You can see that in this chart from Gallup about trust on domestic issues.

Gallup_trust_1

Note that during the George W. Bush administration, Democrats had a lot less trust than Republicans in the federal government on domestic issues. That switched the year President Obama was elected. Then it was Republicans who had a lot less trust in the federal government.

The same holds true on international issues.

Gallup_trust_2

Indeed, more people have confidence in the government now than they did during the bird flu scare in 2005. And about the same percentage are worried about Ebola as were worried about the swine flu in 2009.

We haven’t seen any evidence yet that Ebola has had a substantial effect on the midterm elections. Republican chances of taking the Senate have crept up over the past few days, to 65 percent in FiveThirtyEight’s latest Senate forecast. But the forecast is still within the range it has been all year.

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The 2014 World Series begins Tuesday night, featuring a pair of unlikely combatants in the 89-win Kansas City Royals and the 88-win San Francisco Giants.

How unlikely? The Royals rank as the third-most unexpected pennant winner since 1969 — trailing only the 2008 Tampa Bay Rays and 2006 Detroit Tigers — according to our Weighted Average Loss Total metric. And while the Giants have won a pair of championships in the last five seasons, their cumulative record over the past two seasons has barely cracked .500.

The fact that San Francisco and Kansas City combined for just 177 regular-season wins this year, the fourth-fewest by any pair of World Series opponents ever, has not been lost on the blogosphere. Amid the usual TV-ratings-fueled hand-wringing over whether baseball is or is not dying (it’s not), the Internet also spent the past several days worrying about whether this is the worst World Series ever (or, alternatively, angrily defending the matchup, or just wondering why we care about the teams’ regular-season records in the first place).

For the statistically inclined, it’s an interesting series, if not simply from a philosophical point of view. It’s true that these teams probably aren’t the best two in baseball, and that has led to what Daniel Meyer of Beyond the Box Score called an “existential crisis” for some fans:

“What is the point of it all?” and “Why even play 162 games?” are questions being thrown around as we all lament the reality of a World Series without Mike Trout or Clayton Kershaw.

But in the same article, Meyer notes that Major League Baseball’s regular season (not even the playoffs, which are almost universally regarded as a crapshoot, but the 162-game regular season) is too short to definitively allow the best team to stand out from the pack. Even if MLB expanded to a schedule of 1,000 games per team (!!), the true best team in baseball would have less than a 54 percent chance of producing the regular season’s best record.

Along the same lines, there’s the classic Bill James simulation from the 1980s estimating that the best team in baseball only wins the World Series a little more than 29 percent of the time. And more recent research by Dr. Jesse Frey of Villanova University found that in a typical MLB season we can’t be more than about 40 percent confident in the identity of baseball’s best team anyway.

In other words, there’s a lot of ambiguity, from start to finish. While it seems unlikely that a team like the Royals or the Giants could secretly be baseball’s best despite unimpressive regular-season records, we don’t really know for sure — and besides, the playoffs aren’t a scientific experiment designed to conclusively identify baseball’s best team (otherwise, they’d look like this).

Embrace the uncertainty, and just enjoy this World Series as a showdown of two good, evenly matched teams. After all, there’s a 100 percent chance this matchup will contain the 2014 MLB champion.

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In early September, the story of Ray Rice assaulting his then-fiancée in an Atlantic City casino exploded in the media, sparking a debate about how to prevent — and respond to — domestic violence in the NFL and society at large. But why September? The actual assault happened in February, and yet it took almost seven months for media coverage to reach its height, according to a search of Lexis-Nexis.

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The answer is simple: On Sept. 8, TMZ released the video of the assault, which brought the story back into the news. But even then, our attention spans — perhaps unsurprisingly — are short. Here’s a more detailed look at the media coverage that Rice, as well as the overall issue of domestic violence in the NFL, has received since the beginning of September.

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For the week following the video’s release, articles mentioning “Ray Rice” averaged about 1,900 per day, according to Lexis-Nexis; articles mentioning both “domestic violence” and “NFL” averaged nearly 1,120 per day. The past week, however, pales in comparison: “Ray Rice” has been written about 37 times per day, and “domestic violence” and “NFL” have been mentioned in 44 articles per day. This is despite news that Rice could be reinstated as soon as next month.

Rather, NFL news is back to covering on-the-field events. For example, Google Trends shows news about Peyton Manning has been chugging along at about the same rate (not including the recent surge in coverage of his breaking the career touchdown record) and has overtaken headlines about Rice.

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The fleeting public outrage was enough to force the NFL to reconsider its personal conduct policy, but the league hasn’t yet codified many policies. Public pressure to do so, meanwhile, along with the media spotlight, has largely disappeared.

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