Question

Can anyone help me? I"ll medal and thank you

Answer 1

@Michele_Laino

Answer 2

here you have to apply the formula, which gives the value of \(r\)

Answer 3

how would you take into the formula then?

Answer 4

im confused becasue I dont understand how that works exactly

Answer 5

you have to substitute your numerical data. More precisely, you have 5 ordered pairs, so we can write this:
\[\begin{gathered}
{x_1} = 0.31 \hfill \\
{x_2} = 0.85 \hfill \\
{x_3} = 1.26 \hfill \\
{x_4} = 2.47 \hfill \\
{x_5} = 3.75 \hfill \\
\end{gathered} \]
and analogously for y's:
\[\begin{gathered}
{y_1} = 0.82 \hfill \\
{y_2} = 1.95 \hfill \\
{y_3} = 2.18 \hfill \\
{y_4} = 3.01 \hfill \\
{y_5} = 6.07 \hfill \\
\end{gathered} \]

Answer 6

ok im with you on this so far

Answer 7

thats five for x and y

Answer 8

Yes! do you know the formula of \(r\)?

Answer 9

https://people.richland.edu/james/lecture/m170/ch11-cor.html

Answer 10

yes thats it right?

Answer 11

please wait I retrieve my textbook

Answer 12

I have this formula:
\[\Large r = \frac{{\sum {\left( {x - \bar x} \right)\left( {y - \bar y} \right)} }}{{{{\left\{ {\sum {{{\left( {x - \bar x} \right)}^2}\sum {{{\left( {y - \bar y} \right)}^2}} } } \right\}}^{1/2}}}}\]

Answer 13

of course, all summations run from 1 to 5

Answer 14

furthermore with the symbol \({\bar x}\) I mean the mean value

Answer 15

hmm and so we use this for the formula of r

Answer 16

Yes!
here is my reference textbook:
\[\begin{gathered}
{\text{An Introduction to Error Analysis}}{\text{.}} \hfill \\
{\text{The Study of Uncertainties in Physical Measurements}} \hfill \\
\end{gathered} \]
Author: John R. Taylor
Publisher: University Science Books

Answer 17

of course I have the italian translation

Answer 18

but what could we imply that we put in for the answers?

Answer 19

the third answer depends on the value of \(r\). At the moment, without such value of \(r\) I can not say anything

Answer 20

I guess that \(r\) is close to unit, nevertheless it is only a conjecture

Answer 21

please try to compute the value of \(r\) with my formula above, and then tag me

Answer 22

so would a correct answer for B be the answer of the formula?

Answer 23

How far did you get ?

Answer 24

currently im guessing B is asking that the foumla is the answer? correct?

Answer 25

I interpret it as asking for the numerical value for r
which means you have to calculate it

I would use Michele's formula posted up above.
the first step is find the average x value and the average y value

Answer 26

ok im working on it now

Answer 27

ok so i worked some with a cal and on paper and got .717

Answer 28

I think it should be closer to 1, but I have not calculated it.

Answer 29

did you do it in your head?

Answer 30

It looks like a straight line can go through most of the points.

Answer 31

which formula are you using ?

Answer 32

im using the one i did http://www.rtmsd.org/cms/lib9/PA01000204/Centricity/Domain/197/Key_3.2_Correlation_Homework.pdf

Answer 33

that r=0.97 looks good

Answer 34

I got r=0.967

Answer 35

If I were estimating it, I would guess about 0.9
because the dots almost all lie on the same line, except for one dot
a perfect line has r=1
because it's not perfect I would guess 0.9 (but it's just a guess)

Answer 36

yeas I"ll go with 0.97 for rounding reasons

Answer 37

hmm