2 SAMPLE T TEST MINITAB CODE

'T-Test of difference = 0 (vs ): T-value = P-value = DF = ' If you performed a test with alternative 'greater than' or 'less than' : 'C% lower bound for difference ' This is the value for which we can say 'We can say, with C% confidence that the mean is no less than ' - this is the cutoff for a one-sided confidence interval (all the risk on one side). Output in the Session window:: A heading 'Two-Sample T-Test and CI: ,' A second text line 'Two sample T for vs ' A table with data on the two samples: First a heading line identifying the numbers below For each variable: the variable name, the sample size (labeled 'N'), the sample mean (labeled 'Mean'), Sample standard deviation (labeled 'StDev') and the (sample) standard error of the mean (StDev/sqrt(N) - labeled 'SE Mean).Ī statement of which way the comparison is done: 'Difference = mu - mu'Ī line 'Estimate of difference: ' - this is the difference in the sample means (order as specified in the line above).įor a standard confidence interval (or if the test is 'not equal') 'C% confidence interval for difference: (, ) Click 'OK' for the 'options' window and 'OK' for the '2-sample t' window. If you want to test a null hypothesis of the form 'Mu(1) - Mu(2) = K' (rather than the usual Mu(1) = Mu(2)) enter K in the ' Test Mean' box (usually you will leave this at 0.0) 9. If you want to perform a test on the mean difference: select the alternative hypothesis ('less than' 'not equal' or 'greater than' in the 'Alternative' box - for the one-sided alternatives, make sure the alternative says what you mean (the 'First' and 'Second' labels matter) 8. If you want a confidence interval for the difference between the means: type in the confidence level in the ' Level' box and make sure the ' Alternative' is set to ' not equal' 7. With the cursor in the box labeled ' Second ', select the name of your second variable (or type its name in the box - this is your 'X2'). Remember that the order matters (must match your alternative hypothesis, or the order in which you want to state your results, for estimation - this is your 'X1', if you haven't used better names). With the cursor in the box labeled ' First ', select (double-click or highlight & then click ' Select ') the name (or column) of your first variable (or type the name in the box). Select (click on the circle next to) 'Samples in different columns ' 3. Naming the columns will be a great help here, becauseyou will need to remember which population (which sample) youhave first in your alternative hypothesis or in calculating thedifference for the confidence interval. If the data are in two separate columns - one for each sample.

2 SAMPLE T TEST MINITAB CODE

The data for the two samples are in the same column, with another column containing a code saying which sample the individual is in Procedures for both cases will be disucssed here.ġ.

The data for the two samples are in separate columns (typical if you did an experiment or observation just for this variable)Ģ. You need to know which way the data are entered. Hypothesis tests and Confidence Interval calculations are carriedout with the same command. (Independent samples from two populations) Minitab: Inference on a difference of means Introduction to MINITAB in the Saint Mary's MicrocomputerLab IX.

2 sample t test minitab