[R] Your help plz - (statistical problem)

[K.V.ANANTHA PADMANABHA]

Hi David,

Please help me out to resolve the following
statistical problem.

For the following data 

X         Y
0        21.5
0        21.78
0.03     21.5
0.09     16.3
0.27     9.9
0.81     6.13
2.43     5.17

How to put the logistic curve was fitted for the
following model

          C
Y = --------------
      (1 + (X/X0)^b)


Where Y is the total no. of juveniles per parent
animals alive at the end of the test and X is the
concentartion.

C = the expected no. of juveniles when X = 0
X0 = the EC50 in the population
b = the slope parameter



I expect the results as early as possible.

Thanks & regards

K.V.Anantha Padmanabha
Rallis India Limited