Thread: I dont get this..i need help

1. I dont get this..i need help

The scores for players' first and second games at a bowling tournament are shown below.
First Game Second Game
169 175
150 162
202 195
230 241
187 185
177 235
164 171

a. Determine the correlation coefficient.
b. Find the equation of the line of best fit analytically.

2. Originally Posted by nithujaa
The scores for players' first and second games at a bowling tournament are shown below.
First Game Second Game
169 175
150 162
202 195
230 241
187 185
177 235
164 171

a. Determine the correlation coefficient.
Hi there, you should assign your first list to be your X values and second to be your Y values, now check out this link.

Pearson product-moment correlation coefficient - Wikipedia, the free encyclopedia

That gives you the formula for 'r' the correlation coefficient you are after.

first find mean of X and Y then the standard deviation of X and Y.

To do the calcs I suggest you make a table with the following field headings.

X, X-meanX, Y, Y-meanY

3. Originally Posted by nithujaa
The scores for players' first and second games at a bowling tournament are shown below.
First Game Second Game
169 175
150 162
202 195
230 241
187 185
177 235
164 171

a. Determine the correlation coefficient.
b. Find the equation of the line of best fit analytically.
Surely you can use technology - just enter the given data into an appropriate software package or use a calculator that can do linear regression.

If you have to do it by hand, my first piece of advice is to go to your textbook or class notes and look up the required formulas. Then start doing the required calculations. It is a simple mechanical but tedious process. If you are stuck somewhere in this process, please show what you've done and where you get stuck.

There is a difference between "I can't do it because it is intellectually difficult" and "I can't do it because it is tedious and I just can't face doing all those calculations". Your question falls into the latter category.

4. i got part a as the answer 0.73992 and dont get part b..i still need help with part b..and need to show the work for it.

Correlation(r) = NΣXY - (ΣX)(ΣY) / Sqrt([NΣX2 - (ΣX)2][NΣY2 - (ΣY)2])
-thats the equation i used for part a

the equation that you are supposed to use for part b to find the equation of the line of best fit analytically is..
y=ax+b, where a=n(Σxy)-(Σx)(Σy)
---------------------
n(ΣX2)-(Σx)2
_ _
b=y-ax