Stat Quiz 200 week 1

ADHD Treatment (AT) case study

This study investigated the cognitive effects of stimulant medication in children with mental retardation and Attention-Deficit/Hyperactivity Disorder. This case study shows the data for the Delay of Gratification (DOG) task. Children were given various dosages of a drug, methylphenidate (MPH) and then completed this task as part of a larger battery of tests. The order of doses was counterbalanced so that each dose appeared equally often in each position. For example, six children received the lowest dose first, six received it second, etc. The children were on each dose one week before testing

This task, adapted from the preschool delay task of the Gordon Diagnostic System (Gordon, 1983), measures the ability to suppress or delay impulsive behavioral responses. Children were told that a star would appear on the computer screen if they waited “long enough” to press a response key. If a child responded sooner in less than four seconds after their previous response, they did not earn a star, and the 4-second counter restarted. The DOG differentiates children with and without ADHD of normal intelligence (e.g., Mayes et al., 2001), and is sensitive to MPH treatment in these children (Hall & Kataria, 1992).

Design Issues

This is a repeated-measures design because each participant performed the task after each dosage.

Descriptions of Variables

Variable Description

d0   Number of correct responses after taking a placebo

d15 Number of correct responses after taking .15 mg/kg of the drug

d30 Number of correct responses after taking .30 mg/kg of the drug

d60 Number of correct responses after taking .60 mg/kg of the drug

18. (AT) What is the dependent variable? On what scale (nominal, ordinal, interval,ratio) was it  meared?

X = number of days a Lake Tahoe Community College math student is absent

52. The instructor’s sample produces a mean number of days absent of 3.5 days. This value is an example of a:

a. parameter.

b. data.

c. statistic.

d. variable.

90. Seven hundred and seventy-one distance learning students at Long Beach City College responded to surveys in the 2010-11 academic year. Highlights of the summary report are listed in

Have computer at home    96%

Unable to come to campus for classes  65%

Age 41 or over    24%

Would like LBCC to offer more DL courses    95%

Took DL classes due to a disability    17%

Live at least 16 miles from campus     13%

Took DL courses to fulfill transfer requirements 71%

a. What percent of the students surveyed do not have a computer at home?

b. About how many students in the survey live at least 16 miles from campus?

c. If the same survey were done at Great Basin College in Elko, Nevada, do you think the percentages would be the same? Why?