Confidence Interval on Linear Combination of Means, Independent Groups (5 of 5)


Summary of Computations
  1. Compute the sample mean (M) for each group.

  2. Compute the sample variance (s²) for each of the k groups.

  3. Find the coefficients (a's) so that Σ aiμi is the parameter to be estimated.

  4. Compute L = a1M1 + a2M2 + ... + akMk

  5. Compute MSE = Σs² /k

  6. Compute

  7. Compute df = k(n-1) where k is the number of groups and n is the number of subjects in each group.

  8. Find t for the df and level of confidence desired using a t table

  9. Lower limit = L - t sL

  10. Upper limit = L + t SL

  11. Lower limit ≤ Σaiμi ≤ Upper limit

  1. All populations are normally distributed.

  2. All population variances are equal (homogeneity of variance)

  3. Scores are sampled randomly and independently from k different populations.

  4. The sample sizes are equal.