E-CodeNormal approximation to the binomial — a TI-84 Plus CE program
NORMAPPX is a TI-BASIC program for the TI-84 Plus CE. P(a ≤ X ≤ b) for a binomial, exactly and by the normal approximation with and without the continuity correction, the errors of each, and whether np and n(1-p) are both at least 10.
What it asks for and what it shows
It asks for 4 values at its prompts. In the example below it shows EXACT, CC, PLAIN, ERR C, ERR P, NP,NQ≥10: OK.
Example run
One of its oracle test cases: “100 coin flips, 45 to 55 heads”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Input 1 | 100 |
| Input 2 | 0.5 |
| Input 3 | 45 |
| Input 4 | 55 |
| The screen shows | |
EXACT= | 0.7287469759 |
CC= | 0.7286678781 |
PLAIN= | 0.6826894921 |
ERR C= | 7.909781893E-5 |
ERR P= | 0.04605748379 |
| Text | NP,NQ≥10: OK |
How it's checked
4 test cases, each checked against an independent method. Replayed key by key on a virtual TI-84 Plus CE, they make 27 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-84 Plus CE calculator and pick “Normal approximation to the binomial” (NORMAPPX).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- Binomial, Poisson and normal probabilities
- Geometric distribution: first success
- Regression: linear, quadratic, exponential with r²
- Hypothesis tests: z, t, two-sample t, chi-square
- Confidence intervals: z, t, proportion, two-sample
All TI-84 Plus CE statistics programs · All TI-84 Plus CE programs