delta method

  1. D

    Estimating the probability of the residual lifetime based on Kaplan-Meier curve

    So I had this question on my exam about survival analysis and I didn't know the answer but I would like to know how I should answer it: "Give, based on this KM-curve, an estimate for the probability that the residual lifetime is larger than 300 days, when the patient is already standing on the...
  2. R

    Delta method

    I was wondering if anybody can help me as I've been stuck on this problem for ages and my attempts seem to all be incorrect so far. I have four estimators (W,Χ,Y,,Z) and standard errors for each. How can the standard error of D be cacluated from the following equation, where K, and L are...
  3. A

    Variance of a corrected regression coefficient

    Ppl I really need help! Please, help me solve it: Consider the model Yi = b0 + b 1Xi +ei e_i~N(0,s^2_e) iid X_i_N(m_x,s^2_x) iid Z_i = X_i + u_i, u_i~ N(0,s^2_u) independent of Xi Suppose we have the following data: a. A sample M of n units where Y_i, X_i, Z_i obey the above model...