The Two Conditions for a Valid Instrument Are

question 15

Multiple Choice

The two conditions for a valid instrument are

• A)corr(Zi,Xi)= 0 and corr(Zi,ui)≠ 0.
• B)corr(Zi,Xi)= 0 and corr(Zi,ui)= 0.
• C)corr(Zi,Xi)≠ 0 and corr(Zi,ui)= 0.
• D)corr(Zi,Xi)≠ 0 and corr(Zi,ui)≠ 0.

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Definitions:

Decay Theory

A theory suggesting that memory fades and becomes less accurate over time due to the mere passage of time, leading information to "decay."

Sensory Memory

The shortest-term element of memory, which allows the retention of impressions of sensory information after the original stimuli have ended.

Short-term Memory

The power to hold a minimal amount of details in a readily accessible state for a limited period.

Long-term Memory

The aspect of memory in which information is stored for extended periods, ranging from several minutes to a lifetime.