Justin Wolfers - Faculty Research in Knowledge@Wharton

The Use -- and Misuse -- of Statistics: How and Why Numbers Are So Easily Manipulated

Wed, 02 Apr 2008 17:52:07 EST

When a report prepared by former Senator George J. Mitchell indicated that Roger Clemens and others used illegal, performance-enhancing drugs, a marketing agency prepared a voluminous report that relied on statistics to make the case for Clemens' innocence. But an article written by four Wharton faculty -- Justin Wolfers, Shane Jensen, Abraham Wyner and Eric Bradlow -- questions the methodology used by the marketing agency, noting that the validity of any statistical analysis is only as good as its individual components. And these components, they add, can be easily misinterpreted.

Polling the Polling Experts: How Accurate and Useful Are Polls These Days?

Wed, 14 Nov 2007 15:20:43 EST

Turn on the Internet, pick up your telephone or cell phone, read a newspaper or watch television: No matter what the communication vehicle is, polls and the reporting of poll results are ubiquitous. Yet how accurate are polls? Can they be manipulated? How do the Internet and the proliferation of cell phone users affect both marketing and political polls? And which polls are the most reliable? Knowledge@Wharton interviewed the experts.

On the Fence: Are Illegal Immigrants Good or Bad for the U.S. Economy?

Wed, 13 Jun 2007 14:33:58 EST

Last week, the United States' first major immigration reform bill in two decades collapsed in the Senate. Buried in the ongoing debate was the potential economic impact of a measure that could change the composition of America's workforce in significant ways: By cracking down on illegal immigration, the legislation could constrict the future supply of low-skilled workers, while a move to skill-based visa evaluations could provide more workers for booming high-tech industries. Meanwhile, it isn't exactly clear what impact the country's 12 million illegal residents have on its economy. Experts from Wharton and elsewhere weigh in.

I Do's and Don'ts: How Changes in Marriage, Divorce and Childbirth Are Redefining the Workplace

Wed, 07 Mar 2007 14:51:20 EST

According to a new study by Wharton professors Betsey Stevenson and Justin Wolfers, marriage and divorce rates in the United States are both at historic lows. When Stevenson and Wolfers began to analyze the changing market forces behind these new statistics, one thing became clear: The same forces that play a role in marriage and divorce statistics -- namely birth control, partial closing of the gender wage gap, the rising age of first marriages and dramatic changes in home technologies -- have also had a significant impact on businesses and employees.

Heading for the Fast Track? New Studies Examine Who Gets Promoted and Why

Wed, 10 Aug 2005 15:55:55 EST

Even as two big labor unions decided this week to defect from the AFL-CIO, claiming that it had failed to stop declining union membership or push hard enough for labor reform, debate about the alchemy of promotion -- who gets it, when and why -- animated a recent conference at Wharton organized by the School's Center for Human Resources. Labor economists and human resource specialists attending the conference, entitled "Careers and Career Transitions: New Evidence for a New Economy," tackled a number of issues, including whether or not a "fast track" really exists, the effect of corporate restructurings on professional advancement and the likelihood of promotion for insiders vs. recent outside hires.

The Wi-Fi Debate: Should Cities Be in the Business of Broadband?

Wed, 01 Jun 2005 17:22:46 EST

The city of Philadelphia's grand experiment to blanket its 135 square miles with wireless high-speed Internet access is being closely watched by municipalities across the U.S. that are pursuing similar initiatives. While Philadelphia's project, which edged closer to reality with an announcement on April 7, is more than a year away from completion, it has sparked an intense debate over such questions as: Are broadband services better handled by the public or private sector? Can a wireless broadband network, commonly known as Wi-Fi, be used to help more low-income people gain online access? Should Internet access be viewed as city infrastructure, like telephone poles or city streets?

How Credible Are Polls? Is There a Better Way to Predict Outcomes in Politics and Business

Wed, 03 Nov 2004 16:54:35 EST

This election year's hard-fought presidential race has brought increasing focus on the credibility and methodology of polls - a focus that could have implications for politics, but also for business forecasting, according to Wharton faculty. With growing uncertainty about the value of polls, people are looking more closely at new ways to predict election outcomes - including the use of aggregate poll results, expert opinion surveys and betting markets. "My guess is that polls are the least accurate way of gauging an election," says Wharton marketing professor J. Scott Armstrong.