Suppose X and Y Are Random Variables Whose Density Function

question 121

Multiple Choice

Suppose X and Y are random variables whose density function is given by $f ( x , y ) = \left\{ \begin{array} { c l } 0.2 e ^ { - ( 05 x + 0.4 y ) } & \text { if } x \geq 0 , y \geq 0 \\0 & \text { otherwise }\end{array} \right.$ is a joint density function.

• A)0.2
• B) \(\frac { 1 } { e }\)
• C)0.25
• D)1
• E) \(\frac { 1 } { 2 e }\)
• F) \(\frac { 1 } { \sqrt { e } }\)
• G)0.1
• H)0

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Definitions:

Curve Of Forgetting

A graph that illustrates the decline of memory retention over time, where information is lost exponentially if no effort is made to retain it.

Long-Term Memory

The phase of the memory system that is capable of storing information for long periods of time, often throughout a person's life.

Interference Theory

A theory suggesting that the ability to remember information is affected by other information learned either previously or subsequently.

Proactive Interference

is a phenomenon where older memories inhibit the ability to remember new information because of the clutter or confusion of old and new information.