Mathematics, 31.12.2019 00:31, munozjosue258

If the coefficient of determination is 0.25 and the sum of squares residual is 180, then what is the value of ssy?

a. 60
b. 180
c. 240
d. 800

Answers: 3

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answered: shay9152

And then $SSY=SS_{total}=\sum_{j=1}^n (y_j-\bar y)^2 =240$

C. 240

Step-by-step explanation:

Previous concepts

Analysis of variance (ANOVA) "is used to analyze the differences among group means in a sample".

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.

If we assume that we have independent variables and we have $j=1,\dots,j$ individuals, we can define the following formulas of variation:

$SS_{total}=\sum_{j=1}^n (y_j-\bar y)^2$

$SS_{regression}=SS_{model}=\sum_{j=1}^n (\hat y_{j}-\bar y)^2$

$SS_{error}=\sum_{j=1}^n (y_{j}-\hat y_j)^2 =180$

And we have this property

$SST==SSY=SS_{regression}+SS_{error}=SSR+180$

If we solve for SSR we got:

SSR= SSY-180 (1)

And we know that the determination coefficient is given by:

$R^2 = \frac{SSR}{SSY}$

We know the value os R^2= 0.25 and we can replace SSR in terms of SSY with the equation (1)

$R^2 =0.25= \frac{SSY-180}{SSY}= 1-\frac{180}{SSY}$

And solving SSY we got:

$\frac{180}{SSY}=1-0.25=0.75$

$SSY= \frac{180}{0.75}=240$

And then $SSY=SS_{total}=\sum_{j=1}^n (y_j-\bar y)^2 =240$

C. 240

answered: Guest

The answer is that the rate of change is $50 per 1 monthhope this ; )

answered: Guest

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1