Question

A researcher interested in finding a simple way to estimate intelligence decides to evaluate skull circumference as a possible indicator of intelligence. He finds that the size of an adult's skull remains the same from one measurement to the next, but he finds that skull circumference is not a very good predictor of intelligence. In this example, skull circumference as a measure of intelligence is

A) reliable and valid
B) reliable but not valid
C) valid but not reliable nor valid
E) highly correlated with intelligence test scores

Answer 1

Skull circumference is a reliable measurement (consistent results across time) but is not valid for estimating intelligence since it does not accurately reflect cognitive abilities.

Step-by-step explanation:

In the context of psychological research, the measure of skull circumference as an indicator of intelligence is found to be reliable but not valid. This means that while the size of an adult's skull is consistent over time (reliable), it does not accurately measure or predict intelligence (valid). The Encephalization Quotient (EQ) and cognitive performance are more complex indicators of intelligence that take into consideration factors like brain mass relative to body size, the number of cortical neurons, and neural connections.

Answer 2

B) reliable but not valid

Step-by-step explanation:

The procedure can be considered reliable as the measurement of the skull circumference can be conducted with consistency. Hence, the measurement of the skull circumference can be relied upon for a research. However, the aspect that it can be considered or used as a measure of intelligence does not seem logical or acceptable. Hence, the validity of the procedure is not confirmed since it is stated in the question that "but he finds that skull circumference is not a very good predictor of intelligence". There the procedure is reliable but not valid.