What are interitem correlations? What is their purpose in an item analysis?
What will be an ideal response?
• An interitem correlation matrix displays the correlation of each item with every other item.
• Interitem correlation matrix are usually made up of phi coefficients, which are the result of correlating two dichotomous (having only two values) variables.
• These coefficients are interpreted like Pearson product–moment correlation coefficients.
• The interitem correlation matrix provides important information for increasing the test’s internal consistency. Ideally, each item should be correlated with every other item measuring the same construct and should not be correlated with items measuring a different construct.
• Items that are not correlated with other items measuring the same construct can be dropped to increase internal consistency. An item that does not correlate with other items (developed to measure the same construct) is probably measuring a different construct from that being measured by the other items.
• In practice, interitem correlations tend to be relatively small in size, often in the .15 to .20 range, except for those items that are simple restatements of one another.
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At the very back of the cerebral cortex are the _________ lobes
a. frontal b. parietal c. temporal d. occipital
When infants take an action and modify their next action by watching what happened, this is called
A) intentionality. B) cause and effect. C) trial and error. D) object permanence.
Broca proposed that damage to the language center in the left frontal lobe:
a. is more likely to produce disruption of speech in right-handed persons b. contains neurons that analyze speech for meaning c. disrupted the motor instructions for vocalizing words d. coordinates speech articulation in concert with breathing
________________ memories are retrieved without conscious effort.
A. Semantic B. Iconic C. Implicit D. Echoic