Answer:
Step-by-step explanation:
Hello!
Given the regression equation
Credit= 17.9 - 0.09 Work
That was estimated from a sample of n= 21 statistic students.
Y: number of college credits taken
X: number of hours worked per week at an outside job
a)
The estimation for the slope is -0.09
As you see the estimated slope is negative, this means that the association between the two variables is indirect or inverse. Meaning, when the number of Work increases, the number of Credit decreases. (negative regression)
The correct option is: "An increase in the number of hours worked per week decreases the expected number of credits."
b)
The estimation for the intercept is 17.9
In general, the intercept is the estimated average of Y when X=0. You can interpret the intercept of this equation as "the value of Credits earned by a student that does not work outside of school"
The correct option is: " The intercept is meaningful as a student may not have a job outside of school. "
c)
If Work=0, then Credit= 17.9 (As explained in item b)
By replacing the value in the equation: Credit= 17.9 - 0.09 * 0= 17.9
If Work=60, you replace it in the equation and:
Credit= 17.9 - 0.09 Work= 17.9-0.09*60= 12.5
If the student works 60 hs outside of school it is expected that he takes 12.5 college credits.
I hope this helps!
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