List 1 source of measurement validity evidence from the Standards of Educational and Psychological Measurement AND briefly described how the evidence is collected..

 The poly A tail added to pre-mRNA. 

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 scale of measurement of the independent variable(s)?

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)?

A researcher investigated the impact of a parent losing a job on 7th grade children’s math achievement.  The researcher compared the math achievement of 7th grade children who had 1 parent losing a job with the math achievement of 7th grade children who did not have a parent losing a job.  The researcher hypothesized that when a parent lost a job  children would become more stressed and this stress would hurt the children’s math achievement. In this study, what type of variable is children’s stress levels?

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

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 specific statistical procedure (technique) would you use to test the null hypothesis for this study?

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?