Which of the following would be an example of a design that examines the effects of gender and socioeconomic status (i.e., high, medium, and low) on a test of student achievement?
1) Conducting a study where students from different genders and socioeconomic backgrounds are randomly assigned to different test conditions
2) Analyzing existing data on student achievement to determine if there are any differences based on gender and socioeconomic status
3) Conducting interviews with students to gather qualitative data on how gender and socioeconomic status may impact their test performance
4) Observing students in a classroom setting and noting any differences in achievement based on gender and socioeconomic status