/// <summary>
/// Tests the null hypothesis that the population mean is equal to a specified value.
/// </summary>
///
public TTest(double[] sample, double hypothesizedMean, TTestHypotesis type)
{
int n = sample.Length;
double x = Accord.Statistics.Tools.Mean(sample);
double s = Accord.Statistics.Tools.StandardDeviation(sample, x);
StatisticDistribution = new TDistribution(n - 1);
Statistic = (x - hypothesizedMean) / (s / Math.Sqrt(n));
if (type == TTestHypotesis.MeanIsDifferentThanHypothesis)
{
PValue = 2.0 * StatisticDistribution.SurvivalFunction(Statistic);
Hypothesis = Testing.Hypothesis.TwoTail;
}
else if (type == TTestHypotesis.MeanIsGreaterThanHypothesis)
{
PValue = StatisticDistribution.SurvivalFunction(Statistic);
Hypothesis = Testing.Hypothesis.OneUpper;
}
else if (type == TTestHypotesis.MeanIsSmallerThanHypothesis)
{
PValue = StatisticDistribution.DistributionFunction(Statistic);
Hypothesis = Testing.Hypothesis.OneLower;
}
}
