This Ferguson, MO police officer is wearing a body camera. How would we know if these cameras change behavior? St. Louis Post-Dispatch/Getty Images This example of a quasi-experiment in the news gives us a lot to think about. The headline reads, "New research shows one big change when cops wear cameras." The story introduced research …
Category: Chapter 13; Quasi-Experiments and Small-N Designs
Would you prefer a bronze or silver medal? An Olympic quasi-experiment
In this podium photo of the men's 400M Freestyle, does the smile of the silver medalist, China's Sun Yang, look happier or less happy than that of the bronze medalist, Italy's Gabriele Detti? Note: The happy gold medalist is Australia's Mack Horton. Photo Credit: Matt Slocum AP Photo In honor of the 2016 Rio Olympics that …
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Preschool in Tulsa: Success story….or not?
Why might it be difficult to study the long-term impact of quality preschool programs? Photo: Shutterstock An NPR feature story recently covered Tulsa, Oklahoma's free preschool program, which began about 10 years ago. Like some other cities around the U.S., Tulsa introduced a free pre-K program, with the goal of helping children from all economic …
Thinking critically about data graphics
There's a fun interactive datagraphic on gallup.com's website. It's called "State of the States." You can select a polling variable, such as "overall well-being," "support for Obama," or "religiosity," and it will show you how each U.S. state scores on that variable. Feel free to take a minute to play with the interactive right now. …
Kids learn through play
Do you think this was the kind of kindergarten play the authors had in mind? Photo: gmutlu/ iStockphoto Kindergarten is in the news. Specifically, teachers, parents, and school administrators are discussing how much time kids should spend in kindergarten just playing. This story tells how some schools are re-introducing water and sand tables into their …
ASU’s “Curtain of Distraction” is a quasi-experiment
Photo: Matt York / Associated Press Arizona State University might not have made it to the final 64 teams playing in the 2015 March Madness tournament, but they deserve a special spot in my blog because this story on ASU's "Curtain of Distraction" provides some great quasi-experimental data. Like many college teams, ASU has a …
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Football, brain injury, and “compared to what?”
Football players who develop cognitive problems cannot ask "compared to what?"--they do not have a comparison group of what symptoms they would have had without their history of playing football. Photo credit: Joe Rimkus Jr. / Miami Herald / MCT / Getty Images Here's a sobering feature story about a former college football player, Ryan …
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Do vacation days harm surgeons? A quasi-experiment
Do surgeons perform better, or worse, after taking a day off? Photo: Altrendo Images / Getty Images. There's a great example of a quasi-experiment in the news. The research question concerned the skills of surgeons. As the story points out, surgeons are similar to musicians, in that their manual dexterity skills develop with constant use …
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Stop using cash, reduce crime?
The Washington Post covered a criminal justice story recently that tracked what happened to crime rates after communities changed the way welfare benefits are distributed. Previously, people received checks for public assistance. After they cashed these checks, they could have become targets of crime. Since the 1990's, however, public assistance benefits have gradually changed, and …
Measuring charter schools
Are charter schools effective? Philadelphia Inquirer columnist Joel Naroff wrote about the data we might use to decide whether charter schools are doing well. He describes the pitfalls of using achievement test scores to measure school effectivness. His article uses the language of multiple regression and internal validity to describe how difficult this process is. …