Correlation

Find the correlation of following data

X     Y

10    20

20    30

30    40

40    50

Solution:

         Real x,y,sumx,sumy,ssqrx,ssqry, spxy, Num , Den, r

         Write(*,*) 'Enter the value of N'

         read(*,*) N

          sumx= 0.0

         sumy= 0.0

          ssqrx= 0.0

         ssqry= 0.0

         spxy= 0.0

         Do j = 1,N

         Write(*,*) 'Enter the value of x',j

         read(*,*) x

         Write(*,*) 'Enter the value of y',j

         REad(*,*) y

         sumx = sumx+ x

         sumy = sumy+ y

         Avex= sumx/N

         Avey= sumy/N

         ssqrx= ssqrx+ x**2

         ssqry= ssqry+ y**2

         spxy=spxy+(x*y)

         End do

         Num= spxy- ((sumx*sumy)/n)

         Den= sqrt((ssqrx-(Avex)**2)*(ssqry-(Avey)**2))

         r = Num/Den

         write(*,*) 'The correlation between x and y is =' , r , ssqrx

         End


hints: her we consider N= 4 because each of the variable has 4 observation.