Dependent Sample t-Test: Sample Size Parameters - Quick Tab

Select the Quick tab of the Dependent Sample t-Test: Sample Size Parameters dialog box to access options to establish the basic parameters for analyzing sample size for the dependent sample t-test.

Fixed Parameters. The entries in the boxes under Fixed Parameters establish the fixed, or baseline, parameters for subsequent power calculations and graphs. Parameters that are not varied explicitly as the independent (X-axis) variables in a graphical analysis will be set equal to these values.

Mu1. In the Mu1 box, enter the mean for the statistical population from which the first set of measurements was sampled.

Mu2. In the Mu2 box, enter the mean for the statistical population from which the second set of measurements was sampled.

N. In the N box, enter the sample size for the analysis, i.e., the number of pairs of observations.

Alpha.  In the Alpha box, enter the type I error rate used in determining the critical value for the t-statistic.

Sigma1. In the Sigma1 box, enter the population standard deviation for the first population sampled from in the analysis.

Sigma2. In the Sigma2 box, enter the population standard deviation for the second population sampled from in the analysis.

Rho. In the Rho box, enter the correlation between the two measurements.

Power Goal. In the Power Goal box, enter the minimum acceptable power, for which a minimum sample size is calculated. If the search for an acceptable sample size is successful, the actual power of the statistical test will be greater than or equal to this value.

Type of Hypothesis. Use the option buttons under Type of Hypothesis to determine the type of null hypothesis tested by the t-statistic.

2-tailed (Mu1 = Mu2). Select the 2-tailed (Mu1 = Mu2) option button to use null and alternative hypotheses of the form

H0: μ1 = μ2 H1: μ1 ¹ m2

1-tailed (Mu1 <= Mu2). Select the 1-tailed (Mu1 <= Mu2) option button to use null and alternative hypotheses of the form

H0: μ1 m2 H1: m1 > m2

1-tailed (Mu1 >= Mu2). Select the 1-tailed (Mu1 >= Mu2) option button to use null and alternative hypotheses of the form

H0: μ1 ³ m2 H1: m1 < m2