The kidneys contribute to homeostasis primarily by regulating:

Protein buffering is largely mediated by:

The major inhibitory neurotransmitter in the CNS is:

Surfactant primarily functions to:

“If I drink coffee then I will feel more awake. Robert did not drink coffee. Robert does not feel awake.”  Which test does this enthymeme fail?    

Why is the dominant color of a website not usually the background color?

Part II (38 points): Class Size and Academic Skills Development (A) 15 points: You created a new, categorical version of the class size measure that organized children into three groups: those in small classes that enroll fewer than 16 students (coded 1); medium classes with 16-24 students (coded 2) and large classes with 25 or more students (coded 3). You conducted three ANOVAs using this three-level measure to explore class-size differences in fall and spring literacy achievement as well as the number of books a child has. In describing the post hoc results, use small class sizes as the statistical comparison group. In addition to describing the results of each ANOVA, are there any signs here of a potential link between class size and student learning? What’s the pattern? 

(C) 3 points: Because Earlham County Public School District has a financially diverse student population and the district is interested in equity, you are interested in whether the relationship between class size and literacy achievement depends on socioeconomic status. You conduct an ANCOVA regression analysis using a dummy variable to represent large classes of 25 or more students as your main predictor, SES, and the interaction between large class size and SES. Does the relationship between SES and literacy development depend on class size? If so, how? (Interpret the interaction term only.)

(B) 20 points: The district’s ultimate question is whether class size is associated with student learning in literacy. You conducted a regression within an Analysis of Covariance (ANCOVA) framework, focused on literacy achievement by using the fall reading score as a baseline covariate. In addition to your focus on the class size estimates, please be sure to also describe the covariate estimates.  

(C) 12 points: You started thinking that the class size variable might be somewhat restrictive, given that it collapses the original class size variable (A1DTOTGN) into only two categories. To understand whether the relationships might differ using A1DTOTGN you ran three correlations with SES, number of books a child has, and literacy test scores. What did you find?