
 STATISTICA Power Analysis 
  Modern statistical practice has placed renewed emphasis on confidence interval estimation, both in planning studies and evaluating their meaning. 
  STATISTICA Power Analysis is unique among programs of its type in that it calculates confidence intervals for a number of important statistical quantities such as standardized effect size (in ttests and ANOVA), the correlation coefficient, the squared multiple correlation, the sample proportion, and the difference between proportions (either independent or dependent samples). 
  These capabilities, in turn, may be used to construct confidence intervals on quantities such as power and sample size, allowing the user to utilize the data from one study to construct an exact confidence interval on the sample size required for another study. 
 www.statsoft.com /products/power_an.html (1154 words) 
