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 Two samples comparison
This module is intended for a detailed analysis of two datasets (two samples). The module offers two analyses: independent samples comparison, and paired samples comparison. Independent samples x, y feature no mutual relationship. They can have different sample sizes, in general. Ordering of the elements of both samples is arbitrary and can be changed without any information loss. Main point of this analysis is to decide, whether the expected values E(x) and E(y) of the two samples are different. Weight of peanuts from two different locations can serve as an example of two independent samples. On each location, a few dozens of the peanuts are selected at random and weighted individually.

Two samples comparison - Pdf manual

Example:
Input data:
 System A System B 4.18 4.43 4.69 5.42 5.23 4.11 4.72 4.84 4.32 5.52 4.43 6.51 4.91 4.74 4.29 4.32 3.89 4.53 4.91 5.42 5.63 6.67 6.08 7.34 2.41 4.48
Input dialog window:

Sample graphical output:
Independent data comparison:

Text output:
 Compare two samples Task name : Sheet36 Significance level : 0.05 Columns to compare : System A System B Sample size : 24 24 Average : 4.477982955 5.078125 Std. deviation : 0.787465729 1.070369937 Variance : 0.620102274 1.145691803 Corr. coeff. R(x,y) : 0.225347432 Variance equivalence test Variances ratio : 1.84758523 Degrees of freedom : 23 23 Critical value : 2.014424842 Conclusion : Variances are EQUIVALENT P-value : 0.074221818 Robust variances test Variances ratio : 1.84758523 Corrected degrees of freedom : 10 10 Critical value : 2.978237016 Conclusion : Variances are EQUIVALENT P-value : 0.173707895 Mean equivalence test for Equivalent varances t-statistic : 2.212532441 Degrees of freedom : 46 Critical value : 2.012895599 Conclusion : Means are DIFFERENT P-value : 0.031933164 Mean equivalence test for Different variances t-statistic : 2.212532441 Corrected degrees of freedom : 42 Critical value : 2.018081703 Conclusion : Means are DIFFERENT P-value : 0.032420484 Godness of fit test (two-sample Kolmogorov-Smyrnov) Difference DF : 0.375 Critical value : 0.392050138 Conclusion : Distributions are EQUAL
Paired data comparison:

 Paired comparison Task name : Sheet35 Significance level : 0.05 Columns to compare : X Y Analysis of difference X - Y Sample size : 29 Average difference : -0.734423981 Confidence interval: -2.585348422 1.116500459 Std. deviation : 4.865992191 Variance : 23.67788001 Corr. coeff. R(x,y) : -0.935498387 Test of difference significance t-statistic : 3.954994177 Degrees of freedom : 28 Critical value : 2.048407142 Conclusion : Differences are INSIGNIFICANT P-value : 0.211599993