Fundamentals of Statistics contains material of various lectures and courses of H. Lohninger on statistics, data analysis and chemometrics......click here for more. 
See also: small samples, large samples, Data Set  Gasoline Samples, Data Set  Bananas  
OneSample tTest
A onesample ttest has to be applied in order to compare the mean of a sample to a predefined target value. It is assumed that the target value is known (or defined) in advance. A typical situation where a onesample ttest would be applied could be as follows: a painrelieving medicine used in a hospital brings relief to the patients within 130 seconds (this number is known from thousands of applications in the past). When introducing a new drug, it is administered to 30 patients and the time until the pain reliever shows an effect is recorded. The mean time until relief is 112 seconds with a standard deviation of 43 seconds. Is there any evidence that the new drug reduces the time until a patient receives relief from pain? In this example we have to test a sample mean (the mean relief time for 30 patients) against a predefined limit. Note that the limit is fixed and wellknown. If the limit were not predefined but obtained from another sample (i.e. another 30 patients receiving the old drug), we would have to apply a twosample test.


Last Update: 20121008