BrainIQ: Brain Size and Intelligence
In MPsychoR: Modern Psychometrics with R

Description Usage Format Source Examples

Willerman et al. (1991) conducted their study at a large southwestern university. They selected a sample of 40 right-handed Anglo introductory psychology students who had indicated no history of alcoholism, unconsciousness, brain damage, epilepsy, or heart disease. These subjects were drawn from a larger pool of introductory psychology students with total Scholastic Aptitude Test Scores higher than 1350 or lower than 940 who had agreed to satisfy a course requirement by allowing the administration of four subtests (Vocabulary, Similarities, Block Design, and Picture Completion) of the Wechsler (1981) Adult Intelligence Scale-Revised. With prior approval of the University's research review board, students selected for MRI were required to obtain prorated full-scale IQs of greater than 130 or less than 103, and were equally divided by sex and IQ classification.

1	data("BrainIQ")

A data frame with 40 individuals and the following 7 variables.

Gender: Participant's gender.
FSIQ: Full Scale IQ.
VIQ: Verbal IQ.
PIQ: Performance IQ.
Weight: Body weight.
Height: Body height.
MRI_Count: MRI pixel count (brain size).

Willerman, L., Schultz, R., Rutledge, J. N., & Bigler, E. (1991). In vivo brain size and intelligence. Intelligence, 15, 223-228.

1 2	data(BrainIQ) str(BrainIQ)

'data.frame':	40 obs. of  7 variables:
 $ Gender   : Factor w/ 2 levels "Female","Male": 1 2 2 2 1 1 1 1 2 2 ...
 $ FSIQ     : int  133 140 139 133 137 99 138 92 89 133 ...
 $ VIQ      : int  132 150 123 129 132 90 136 90 93 114 ...
 $ PIQ      : int  124 124 150 128 134 110 131 98 84 147 ...
 $ Weight   : int  118 NA 143 172 147 146 138 175 134 172 ...
 $ Height   : num  64.5 72.5 73.3 68.8 65 69 64.5 66 66.3 68.8 ...
 $ MRI_Count: int  816932 1001121 1038437 965353 951545 928799 991305 854258 904858 955466 ...