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StatsToDo : Sample Size for Comparing Two Cronbach's Alphas Program

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Explanations Javascript Program R Codes
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 = number of items in Alpha1 (k1)(questions in a factor)
  - Col 4 = Cronbach Alpha1 expected (CA1)
  - Col 5 = number of items in Alpha2 (k2)(questions in a factor)
  - Col 6 = Cronbach 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 = Averaged sample size per Alpha (assuming equal size groups) ((n1+n2)/2)
  - Col 3 = number of items in Alpha1 (K1)
  - Col 4 = Cronbach Alpha1 observed (CA1)
  - Col 5 = number of items in Alpha2 (K2)
  - Col 6 = Cronbach Alpha2 observed (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 = number of items in Alpha1 (K1)
  - Col 4 = Cronbach Alpha1 observed (CA1)
  - Col 5 = number of items in Alpha2 (K2)
  - Col 6 = Cronbach Alpha2 observed (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 : Number of items in the first Alpha (k1)
  - Row 3 : Value of the first Alpha Coefficient (CA1)
  - Row 4 : Number of items in the second Alpha (k2)
  - Row 5 : Value of the second Alpha Coefficient (CA2)
  - Row 6 : Sample size interval for tabulation (usually 3 - 10)
  - Row 7 : Maximum sample size (per Alpha) (Usually <=100)