Question

Between two variables analyzing with basic correlation and regreation with getting at least 11 datas. What Y=? When X=9

(Determine the datas by yourself)

Answer 1

lets assume the data is

X	Y
16	327
36	760
18	383
24	512
38	795
22	469
37	769
28	580
20	417
31	646
30	626
17	361

we will findout correlation with above data

correlation equation is

mean of x

mean of y

	X	Y	a=(Xi-X(mean))	b=(Yi-Y(mean))	a*b	a^2	b^2
	16	327	-10.42	-226.75	2361.98	108.51	51415.56
	36	760	9.58	206.25	1976.56	91.84	42539.06
	18	383	-8.42	-170.75	1437.15	70.84	29155.56
	24	512	-2.42	-41.75	100.90	5.84	1743.06
	38	795	11.58	241.25	2794.48	134.17	58201.56
	22	469	-4.42	-84.75	374.31	19.51	7182.56
	37	769	10.58	215.25	2278.06	112.01	46332.56
	28	580	1.58	26.25	41.56	2.51	689.06
	20	417	-6.42	-136.75	877.48	41.17	18700.56
	31	646	4.58	92.25	422.81	21.01	8510.06
	30	626	3.58	72.25	258.90	12.84	5220.06
	17	361	-9.42	-192.75	1815.06	88.67	37152.56
mean	26.41667	553.75
				sum	14739.25	708.92	306842.25

r = 0.99935 it means direct relation between X & Y

then regression line equation is.

Y = aX +b

a = slope of the equation

c = constant of the equation

	X	Y	XY	X^2
	16	327	5232	256
	36	760	27360	1296
	18	383	6894	324
	24	512	12288	576
	38	795	30210	1444
	22	469	10318	484
	37	769	28453	1369
	28	580	16240	784
	20	417	8340	400
	31	646	20026	961
	30	626	18780	900
	17	361	6137	289
sum	317	6645	190278	9083

N = no of data =12

put above euation

a = 20.791

b = 4.515

Y = 20.791 * X + 4.515

X = 9 then Y = 191.634.