An Item-Discrimination Index Is Used on an Ability Test

question 20

Multiple Choice

An item-discrimination index is used on an ability test

• A) to determine whether items are measuring what they are designed to measure.
• B) to measure the difference between how many high scorers and how many low scorers answered the item correctly.
• C) to estimate how predictive the item is of the testtaker's future performance.
• D) to measure the difference between how many median scorer and how many low scorers answered the item correctly.

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Definitions:

Lesion Method

The removal or disabling of a brain structure to gain better understanding of its function; this method is used only in animals.

Transcranial Direct Current Stimulation

A form of neurostimulation that uses constant, low current delivered directly to the brain area via electrodes on the scalp.

Animals

Multicellular, eukaryotic organisms of the kingdom Animalia that are capable of locomotion, responsive to their environment, and feed by consuming other organisms.

Androgen

A type of hormone that plays a role in male traits and reproductive activity; testosterone is the most well-known androgen.