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StatsToDo : Sample Size for Comparing 2 Means

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Explanations Javascript Program R Codes Sample Size Tables
Data
Sample Size: Data a table of 4 columns
  - Each row contains data from a separate study
  - Col 1 = Probability of Type I Error α
  - Col 2 = Power (1 - β)
  - Col 3 = Difference Between the Two Means to be Detected
  - Col 4 = Expected Within Group Standard Deviation
     

Power: Data a table of 6 columns
  - Each row contains data from a separate study
  - Col 1 = probability of Type I error (α)
  - Col 2 = Differences between group means observed
  - Col 3 = sample size Group 1 used
  - Col 4 = Standard Deviation of Group 1 observed
  - Col 5 = sample size Group 2 used
  - Col 6 = Standard Deviation of Group 2 observed
     

Confidence Interval: Data a table of 5 columns
  - Each row contains data from a separate study
  - Col 1 = Percent confidence (usually 95 or 99)
  - Col 2 = sample size group 1
  - Col 3 = Standard Deviation group 1
  - Col 4 = sample size group 2
  - Col 5 = Standard Deviation group 2
     

Pilot Study: Data is for a single plan, a single column with 4 rows
  - Row 1 = Percent confidence required, usually 95 or 99
  - Row 2 = within Group or pupulation Standard Deviation
  - Row 3 = Sample size intervals
  - Row 4 = Maximum sample size