Benefits of Experimental Research Jeremy M. George CNS 721 BG SP 15 04/04/2015
Proposed Stages to the Experiment Research Question Is the reading program effective? Pretest Random Assignment Control Group Receives regular lecture, practice and assignments to complete for six weeks, no choice of book Comparison Group Small group discussions are added at three weeks Experimental Group Receives regular lecture, practice and assignments to complete for six weeks At three weeks the reading program is added to regular coursework Reading program is an after school program comprised of small group discussion, small group exercises and freedom of book choice (within parameters) Posttest Pretest Random Assignment Control Group A Comparison Group B Experimental Group C Posttest
Random Assignment Guys Girls Sheldon Penny Howard Amy Leonard Control Group A Howard Amy Leonard Bernadette Barry Lucy COMPARISON Group B Experimental Group C Rajesh Leslie Stuart Priya
Dependent and Independent variables Reading Scores Style of Teaching Actively encouraged to read at home Independent Variable A Independent Variable B
Why experimental research? Control over extraneous variables Random Assignment Pretest Co-variates - “adolescents whose parents actively encourage them to read at home” Matching participants Blocking variables Matching treatment conditions Posttest Reduces threats to validity External validity concerns Groups are equated by gender and grade Four group members Two guys and two girls each Keep in mind these numbers are theoretical, and that it is not the number but the distribution that is important in our actual study Groups are representative of population of school Internal validity concerns Boys and girls in each group are matched based on similar maturation rates All boys and girls scored moderately on their pretest All groups receive some kind of benefit (increased letter grade for participation) Outcomes are measurable HYPOTHESIS - those who participate in the after school reading program will score higher post participation Comparison of pretest scores and post test scores will demonstrate if this is true An added benefit is that we will likely see the variance between the effect of small group discussion on the reading scores as well as the effect of small group discussion and book choice on reading scores