E-CodeBinomial (exact), Poisson and normal probabilities — a TI-89 Titanium program
PROB89 is a TI-89 BASIC program for the TI-89 Titanium. Pick a distribution from a pop-up: binomial P(X=k) and P(X≤k) as exact fractions when p is a fraction (105/512), Poisson P(X=k) and P(X≤k), or the normal probability between two values by numeric integration, with mean and SD.
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 P(X=K), P(X≤K), DECIMAL, MEAN, SD.
Example run
One of its oracle test cases: “10 fair coins, exactly 4 heads: 105/512”. 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 | 10 |
| Input 2 | 1/2 |
| Input 3 | 4 |
| The screen shows | |
P(X=K)= | 105/512 |
P(X≤K)= | 193/512 |
DECIMAL= | 0.205078125 |
MEAN= | 5 |
SD= | 1.58113883 |
How it's checked
8 test cases, each checked against an independent method. Replayed key by key on a virtual TI-89 Titanium, they make 49 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 “Binomial (exact), Poisson and normal probabilities” (PROB89).
- 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)
- One-variable statistics of a list
- Linear regression with exact slope
- t test and interval from data lists
- Chi-square goodness of fit
All TI-89 Titanium statistics programs · All TI-89 Titanium programs