Because students often switch schools, the student fixed effect will not subsume the school fixed effect.
Because the model includes student fixed effects, all time invariant characteristics such as race/ethnicity and sex will be captured in the student fixed effects.
However, in their student fixed effects model, percent LEP has a positive association with mathematics achievement.
The author uses school fixed effects and student fixed effects to control for potential non-random sorting of LEP students.
The model includes student fixed effects, school fixed effects, and grade-specific time fixed effects, discussed in more detail below.
The inclusion of student fixed effects controls for any between-student variation that is constant over time, such as innate ability, gender, etc. School fixed effects control for time-invariant differences across the schools.
Tables 2 and 3 contain student fixed effects results for standardized reading (Table 2) and mathematics (Table 3) test scores, where the sample is restricted to non-LEP students.
Vigdor et al. (2014), who also found negative effects of home computer use, used a very powerful approach to control for selection bias based on estimating student fixed effects in longitudinal data.
The student fixes the towel and puts it on the patient's right arm.
