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MeanDifferenceCI


gives a confidence interval for the difference between the population means estimated from and .
  • gives a confidence interval centered at Mean[list1]-Mean[list2].
  • is based on a normal distribution if the population variances are assumed known.
  • If the variances for the two populations are assumed equal and unknown, the interval is based on Student's t distribution with Length[list1]+Length[list2]-2 degrees of freedom.
  • If the population variances are not assumed known and not assumed equal, Welch's approximation for the degrees of freedom is used.
  • The following options can be given:
ConfidenceLevel0.95probability associated with a confidence interval
EqualVariancesFalsewhether the unknown population variances are assumed equal
KnownVarianceNonelist of variances of each population
The 95% confidence interval for the difference in two population means:
Needs["HypothesisTesting`"]
The 95% confidence interval for the difference in two population means:
In[2]:=
Click for copyable input
Out[2]=
The 99% confidence interval:
A confidence interval assuming equal but unknown variances:
A confidence interval assuming known variances: