Help plz:)))I’ll mark u Brainliest

The least-squares regression model y =−3.4+5.2x and correlation coefficient r=−0.66 were calculated for a set of bivariate data

Makovka662 [10]

Answer:

$r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}$

For this case the value of r = -0.66

Now we can calculate the determination coeffcient:

$r^2 = (-0.66)^2 = 0.4356$

And then we can conclude that 43.56% of the variation in y can be explained by the explanatory variable

And then 100-43.56 = 56.44 % of the variation in y that cannot be explained by the explanatory variable

Step-by-step explanation:

For this case we need to calculate the slope with the following formula:

$m=\frac{S_{xy}}{S_{xx}}$

Where:

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}{n}$

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}$

$\bar x= \frac{\sum x_i}{n}$

$\bar y= \frac{\sum y_i}{n}$

And we can find the intercept using this:

$b=\bar y -m \bar x$

And the model obtained for this case is:

$y = -3.4 +5.2 x$

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.

And in order to calculate the correlation coefficient we can use this formula:

$r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}$

For this case the value of r = -0.66

Now we can calculate the determination coeffcient:

$r^2 = (-0.66)^2 = 0.4356$

And then we can conclude that 43.56% of the variation in y can be explained by the explanatory variable

And then 100-43.56 = 56.44 % of the variation in y that cannot be explained by the explanatory variable

8 0

2 years ago

Please help! I will mark brainliest :))

Valentin [98]

First do inside the parenthesis first.

When dividing two exponents subtract them.

15-5 = 10

So w^15 / w^5 becomes w^10

Now you have (w^10)^4

Now multiply the exponents:

10 x 4 = 40

Final answer is w^40

3 0

3 years ago

If you spend 600 rupees per month, that is the amount of loan in 6 months. If he spends 440 rupees per month, he repays the loan

Marta_Voda [28]

Answer:

hjskkdoododkdkdndndndndndndndnsn sorry I needed points to ask a question

8 0

3 years ago

Y is inversely proportional to x

irinina [24]

A ) equation would be X = Z / Y
B ) if X = 9 ------------> Y = 1/7
X = 21 ----------> Y = ?
21*1/7 = 21/7 , 21/7÷9 = 21*9/7 = 27

so Y equal 27

8 0

3 years ago

Read 2 more answers

PLS HURRRRRRRYYYYY TYYY

Ede4ka [16]

Answer:

It's 15.70796. Won't go in-depth since time seems to be of the essence

Step-by-step explanation:

Won't go in-depth since time seems to be of the essence

8 0

2 years ago