What is the independent variable(s) based on this title?   “The Effects of the Amount of Homework on Tenth Grade Students’ End of Course Math Test Scores”    

A researcher was interested in comparing the academic motivation of identified gifted 4th grade students and 4th grade students who were not identified as gifted.   100 gifted 4th grade students and 100, 4th grade students who were not identified as gifted were randomly selected and were administered a 10 item academic motivation questionnaire (Cronbach alpha = .96).  The responses to the questionnaire were combined to form an overall academic motivation score. What is the independent variable(s)?

What is the difference between the B and Beta?  What is the same about B and Beta?

A middle school wanted to evaluate the efficacy of a 6-month after-school program designed to teach 7th grade students math concepts. The program involved weekly sessions that used computer apps that had tutorials and practice problems. Students (n= 100) who were struggling in math (based on 6th grade math scores) were included in the program.  At the beginning of the year the students took a math pretest (reliability = .45) and scored a mean of 15 (out of 100). After 6-months 65 of the 100 students remained in the program.  These 65 students were posttested and scored an average of 45 on the identical test that was used at pretest (out of 100).  The reliability of the posttest was .75. For each threat to internal validity, define the threat and briefly discuss if this threat is likely. Statistical regression

King presents in Table 1 an effect size of 1.33 for the summarizing group’s posttest scores compared to the notetaking group’s posttest score..  Interpret this value

A researcher was interested in comparing the effectiveness of 3 types of instructional materials for teaching 1 biology concept. The instructional materials included: using text materials, video materials, text + video materials.  25 10th grade Biology students were randomly assigned to each type of instructional material for a total of 75 students.  These 75 students were volunteers  recruited from an after-school program.  Students used the method for 1, 2-hour session and were then tested using a 20 item Biology exam. What is the dependent variable(s)?

A researcher was interested in comparing the effectiveness of 3 types of instructional materials for teaching 1 biology concept. The instructional materials included: using text materials, video materials, text + video materials.  25 10th grade Biology students were randomly assigned to each type of instructional material for a total of 75 students.  These 75 students were volunteers  recruited from an after-school program.  Students used the method for 1, 2-hour session and were then tested using a 20 item Biology exam. The researcher used random assignment. List 1 other method the researcher could use to control and reduce extraneous and confounding variables?

What is the dependent variable? The prediction of depression in adulthood from the number of traumatic events experienced by first-generation college students. in childhood.  

If a researcher reported an effect size (Cohen’s d)  comparing the difference between males and females on mathematics of -1.50, what would be your interpretation of the size of the effect?

The Columbian Exchange only had a significant impact on conditions in the New World (North America, Middle America, and South America).  Locations in Europe were not significantly impacted by the exchange of agricultural goods.