Answer:
option A
Step-by-step explanation:
given,
10% A grades 80% B grades 10% C grades
This year, managers with scores less than 35 received C's and those with scores above 425 received A's.
The mean has to be middle of two corresponding cutoff value
μ = 230
Cutoff Off C grade corresponds with the area of 0.10 is table A.
corresponding z- score according to Table A
Z = -1.28
now, standard deviation
σ = 152.3
Correct answer is option A
Answer:
a)Slope:
Intercept:
b)
And the determination coeffecient is
Step-by-step explanation:
Data given and definitions
The correlation coefficient is a "statistical measure that calculates the strength of the relationship between the relative movements of two variables". It's denoted by r and its always between -1 and 1.
The sum of squares "is the sum of the square of variation, where variation is defined as the spread between each individual value and the grand mean"
When we conduct a multiple regression we want to know about the relationship between several independent or predictor variables and a dependent or criterion variable.
n=110,
Part a
The slope is given by this formula:
If we replace we got:
We can find the intercept with the following formula
We can find the average for x and y like this:
And replacing we got:
Part b
In order to calculate the correlation coefficient we can use this formula:
For our case we have this:
n=110,
So we can find the correlation coefficient replacing like this:
And the determination coeffecient is