Forward acceleration is an important factor to control in biomechanics studies investigating walking/running, as human kinetics and kinematics vary with changes in acceleration. During overground running studies, acceleration is typically estimated using the net anterior-posterior ground reaction force impulse, as measured with force plates. However, as studies move outside the lab, there is limited validation of alternative methods of quantifying acceleration when force plates are unavailable. The purpose of this study was to assess the validity of alternative methods for estimating acceleration in overground running. We evaluated the use of timing lights and motion capture, as indicators of acceleration, to measure change in velocity. We hypothesized that the change in velocity calculated from timing lights and motion capture markers near the center of mass would have a strong positive correlation with the relative anterior-posterior ground reaction force impulse measured with force plates. Ten participants ran in an indoor lab while measurements were collected using timing lights, motion capture and a force plate. The correlation between the relative anterior-posterior impulse and velocity changes measured by timing lights was weak (r = -0.01, r = 0.27 and r = 0.15, respectively). In contrast, the correlation between the relative anterior-posterior impulse and velocity change determined by motion capture was strong (r = 0.81). In studies where force plates are not available, measuring changes in velocity with motion capture is a promising method for calculating and controlling acceleration. However, measuring changes in velocity with timing lights does not show as much promise due to weak correlation values and should therefore be avoided.

More than 50 years have passed since the Equal Pay Act of 1964, and women are still paid less than men. United States universities claim to be pioneers of social progress and so it is of interest to know whether the gender wage gap exists there. This study sheds light on the academic gender wage gap by comparing the salaries of male and female assistant professors within three years of being hired at selected U.S. public universities. The group of assistant professors are likely to satisfy our exchangeability assumption because early career faculty tend to come with similar experience. Finally, we focus on public university faculty because their salaries are publicly available. The data studied was collected from salary reports from public university systems in 2018 and 2019 under the Freedom of Information Act. Due to the novel way of assigning gender using genderize.io, traditional statistical methods for comparing two populations are not appropriate. For this reason, this study uses permutation-based non parametric tests that are valid for the data. Our study examines the presence of the gender wage gap in U.S. public universities and finds that significantly more women receive lower salaries than men. For example, the proportion of women making less than $10,000 a month is 12% higher than the proportion of men making the same amount. The study concludes that gender disparities within academic disciplines are a considerable factor contributing to the wage gap.