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.
Authors: Victor Lavy, Edith Sand
What they found: Some teachers underestimate girls’ math ability, and this bias affects girls’ achievement in math and whether they take advanced math classes in middle and high school.
Why it matters: Many more men than women earn science and math degrees, and employment in jobs requiring science and math training is heavily skewed toward men. One explanation might be that teachers systematically overstate the math and science abilities of boys while perceiving girls as academically unfit for those subjects. To test this theory, the authors of this paper followed a cohort of Israeli students from middle school through high school. They compared teacher-graded exams with scores from a national standardized test graded by an independent agency (where the students’ gender was never revealed). The effects on students with biased teachers were huge: Girls’ scores on math tests later in high school suffered, as did their completion of advanced math and science courses. The bias had a greater effect on students whose father had more education than their mother, and on students from low-income families.
Key quote: “Teachers’ biases that favor boys encourage boys to enroll in advanced math courses while doing the opposite for girls; since these courses are prerequisites for admission to higher education in these subjects, such teachers’ stereotypical biases contribute to the gender gap in academic degrees in fields like engineering and computer science, and by implication they also contribute to the gender gap in related occupations.”
Data they used: Administrative records from sixth-grade students in the Tel-Aviv municipality’s school
Authors: Daniel Houser, John A. List, Marco Piovesan, Anya Savikhin Samek, Joachim Winter
What they found: Parents act more dishonestly in front of sons than daughters.
Why it matters: Some studies and experiments have shown that men are more likely than women to act dishonestly — whether it be dodging bus fares in Italy, or failing to return excess change at a restaurant, or intending to cheat on exams. To explain this gender gap, the researchers of this paper devised an experiment to measure how dishonestly parents were willing to behave around their children — in this case, whether they would lie about the outcome of a coin toss to get a benefit (such as a toy for their child). Participants were parent-child pairs, with the kids 3 to 6 years old. The parents lied much less when their child was present. When alone, they were more likely to cheat, especially to get a toy for their child and not a benefit directly for themselves. But to the extent parents acted dishonestly in front of their children, they were more likely to do so around their sons.
Key quote: “One might speculate that adult males are found to lie more often than adult females because, in part, parents constrain their lying behavior to a greater degree under the scrutiny of daughters than sons.”
Data they used: Observations from an experiment involving 152 parent-child pairs in Chicago Heights, Illinois.
Authors: Mikko Packalen, Jay Bhattacharya
What they found: Younger scientists are more likely to try out new ideas in their published papers than older scientists, but some mixed teams of young and old scientists experiment with new ideas even more.
Why it matters: Transformative scientific breakthroughs often come from new, unaccepted ideas. But established scientists often have a vested interest — whether intellectual, economic or social — in older ideas and methods of research. This paper’s authors mined decades of biomedical journals to test whether the age of a scientist had a relationship to the novelty of the ideas expressed in his or her research. Younger scientists were much more likely to be working on new ideas than older scientists: For those less than 10 years into their careers, nearly 10 percent more of their research was devoted to trying out new ideas compared to scientists 40 or more years into their careers. The likelihood of trying out new ideas is by far the highest in the few years after a scientist’s first paper, and then it starts to decline steeply after that. The authors found certain research team arrangements that seemed to produce the most novelty. Specifically, papers with a young scientist as first author and an established scientist as the last author had the highest share of new ideas.
Key quote: “The stereotypical model of a successful scientific team envisions a brash, young scientist — brimming with untested insights — paired together with the wiser, older scientist with the judgment to help guide and encourage the young scientist. Our findings suggest that this model team is indeed fruitful for scientific progress, at least in terms of trying out and playing around with new ideas.”
Data they used: Journal publications in biomedicine back to the mid-1940s.