A If $x=1$ , There Is a Perfect Direct Line Ar Relation Between

question 31

Short Answer

A. If $x=1$ , there is a perfect direct line ar relation between the dependent $Y$ variable and the independent $X$ variable.
B. $\quad R^{2}$ is the proportion of total variation in the independent variables that is explained by the dependent variable.
C. $\mathrm{R}^{2}=75$ when a given regression model is unable to explain $25 \%$ of the variation in the dependent $Y$ variable.
D. When a simple regression model is unable to explain $19 \%$ of demand variation, the coefficient of correlation equals $90 \%$ .
E. In a simple regression model with only one independent variable, the correlation coefficient falls in the range between 1 and 0

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Definitions:

Acetylcholine

A neurotransmitter in the nervous system that plays an important role in muscle contraction, arousal, sleep, and memory.

Night Terrors

Intense episodes of fear that occur during sleep, typically in children, characterized by screaming, sweating, and confusion but little or no recall of the event upon awakening.

Nightmares

Disturbing dreams that can cause feelings of fear, terror, or anxiety, often awakening the sleeper.

Nicotine

The active ingredient in tobacco.