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StatsToDo: Sample Size Comparing Two Cronbach's Alphas

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Explanations and References Javascript Program
Data
Sample Size : is a table of 6 columns
  - Each row contains data from a separate study
  - Col 1 = Probability of Type I Error α
  - Col 2 = Power (1 - β)
  - Col 3, 5 = number of items in Alpha1 (k1) & Alpha2 (k1) (items in a factor)
  - Col 4, 6 = Expected Alpha1 (CA1) & Alpha2 expected (CA2)
  

Power Estimation : is a table of 6 columns
  - Each row contains data from a separate study
  - Col 1 = Probability of Type I Error α
  - Col 2 = Sample size per Alpha (assuming equal size groups) ((n1+n2)/2)
  - Col 3, 5 = number of items in Alpha1 (K1) & Alpha2 (K2)
  - Col 4, 6 = Observed Alpha1 (CA1) & Alpha2 (CA2)
  

Confidence Interval : is a table of 6 columns
  - Each row contains data from a separate study
  - Col 1 = Percent confidence (usually 95 or 99)
  - Col 2 = Sample size per Alpha (assuming equal size groups) ((n1+n2)/2)
  - Col 3, 5 = number of items in Alpha1 (K1) & Alpha2 (K2)
  - Col 4, 6 = Observed Alpha1 (CA1) & Alpha2 (CA2)
  

Pilot Stury : is for a single plan, a single column with 7 rows
  - Row 1 : Percent confidence required (usually 95 or 99)
  - Row 2, 4 : Number of items in the Alpha1 (k1) & Alpha2 (k2)
  - Row 3, 5 : Value of the Alpha1 (CA1) & Alpha2 (CA2)
  - Row 6 : Sample size interval for tabulation (usually 3 - 10)
  - Row 7 : Maximum sample size (per Alpha) (Usually <=100)
  

R Codes