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Calculator: A-priori Sample Size for Student t-Tests
                                    
                                 
                             
                         
                        
                        
                        
                        
                     
                    
                    
                    
                        
                            
                                
                                
                                
                                
                                
                                    
                                    
                                        
                                        
                                        
                                        
                                    
                                    
                                    
    A-priori Sample Size Calculator for Student t-Tests
    This calculator will tell you the minimum required total sample size and per-group sample size for a one-tailed or two-tailed t-test study, given the probability level, the anticipated effect size, and the desired statistical power level.
Please enter the necessary parameter values, and then click 'Calculate'.