E-Codet test and interval from data lists — a TI-89 Titanium program
TTEST89 is a TI-89 BASIC program for the TI-89 Titanium. One-sample or pooled two-sample t test straight from your data lists (drop-down): t, degrees of freedom, two-sided p-value, the decision at alpha, t* and the confidence interval — the t distribution is your own Define'd function (exact finite sums for whole-number df).
What it asks for and what it shows
It asks for 3 values at its prompts, after you pick option 1 from its menu. In the example below it shows T, DF, P, T*, CI LOW, CI HIGH, DO NOT REJECT H0.
Example run
One of its oracle test cases: “one sample, 5 df (odd)”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Menu | option 1 |
| Input 1 | 5 |
| Input 2 | 0.05 |
| Input 3 | {5.1,4.9,5.3,5.2,4.8,5.4} |
| The screen shows | |
T= | 1.233587909 |
DF= | 5 |
P= | 0.2721791032 |
T*= | 2.570581836 |
CI LOW= | 4.873553702 |
CI HIGH= | 5.359779632 |
| Text | DO NOT REJECT H0 |
How it's checked
5 test cases, each checked against an independent method. Replayed key by key on a virtual TI-89 Titanium, they make 39 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-89 Titanium calculator and pick “t test and interval from data lists” (TTEST89).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- One-sample z test and interval (dialog)
- Chi-square goodness of fit
- Linear regression with exact slope
- Least-squares polynomial fit (exact)
- One-variable statistics of a list
All TI-89 Titanium statistics programs · All TI-89 Titanium programs