Question

Whats the regression equation???
Height: 115, 124, 75, 75, 130, 74, 98, 87
Interval after min: 84, 78, 65, 69, 81, 72, 65, 66
Current eruption has a height of 92ft
Use the significance level of 0.05.
ŷ = ( ) + ( )x

Answer 1

looks like a prime candidate for the ti83

Answer 2

but then im not sure what the last line means for this

Answer 3

input your values into list 1 and list 2

there is a function on your ti83 that will then give you the regression line.

Answer 4

otherwise, it gets complicated, but excel or some spreadsheet makes life simpler for us

Answer 5

ok I am trying now

Answer 6

I cant get it

Answer 7

This is my last question that I am having issues with

Answer 8

yeah, its a bit complicated, but listing them is the key ....

by hand, we would need to know more complicated results

sum of x^2
sum of y^2
sum of xy
sum of x
sum of y
average x
average y
and number of ordered pairs.

Answer 9

I tried but I am getting the wrong data input

Answer 10

Please please help me on this one

Answer 11

ive got a spread sheet worked out hold on

Answer 12

Thank you so much!!!

Answer 13

ok, this is what im getting, and ill explain it

Answer 14

Okay thank you bc that looks confusing lol

Answer 15

we want to utilize the point slope formula, our point (avgX, avgY) and a slope that is determined by the formula:
\[m=\frac{n\sum xy-\sum x\sum y}{n\sum xx-\sum x\sum x}\]
as such:
\[\hat y=avgY+m(x-avgX)\]
\[\hat y=avgY-m.avgX~+mx\]
i used the spreadsheet to make all these calculations

m = 2.356

avgY-m.avgX = 268.040

Answer 16

now i dont know what your program is wanting as far as how many decimal places to rnd to

Answer 17

i cut it off at 3 decimals

Answer 18

and I have no idea what this is refering to: Use the significance level of 0.05

Answer 19

So, it should then say ŷ = (2.356 ) + ( 268.04)x

Answer 20

that is what i would use for it, but again, i dont know what your course uses as a rnding of decimals. I used 3 places.

Answer 21

it says two decimal places

Answer 22

ŷ = (avgY-m.avgX ) + (m)x

ŷ = (268.04 ) + ( 2.36)x

Answer 23

Ugh it said it wasn't right

Answer 24

the equation itself is all i can answer to, the rest of it ... i havent a clue about.

Answer 25

did you find the best predicted value?

Answer 26

y^ is the best predictor

Answer 27

when we formulate the regression line, we then use it for x=96

Answer 28

well, 92 in this case

Answer 29

if i had excel, it would allow me to verify the line, but i have something else on this computer ... guess i can use a website

Answer 30

ŷ = (47.87 ) + ( 0.25)x what about from this?

Answer 31

ok, an online calculator says ive got an error in the y intercept

slope is fine tho

Answer 32

got it now, i erred in multiplyng :)

y = m(x-X) + Y

y = mx -mX + Y
^^^^
i ignored the negative of it

Answer 33

this is the correction

y = 2.36x - 73.54