TI-83/TI-84 DIY InvF function
TI-83 and TI-84 calculators lack the inverse F function. Inverse F uses alpha, D1 and D2 degrees of freedom to solve for the critical value in hypothesis tests for 2-population variance and ANOVA.
Here is a simple, 4-line program to add that functionality to your calculator.
Steps to add INVF:
Go to PRGM, NEW, 1. Create New
At the Name= prompt, the cursor is in Alpha mode. Enter a short name such as INVF
ENTER
: Input “AREA RIGHT:”,A
: Input “D1:”,N
: Input “D2:”,D
: Disp solve(1-Fcdf(0,X,N,D)-A,X,0)
:
Click 2nd MODE to quit the program.
Click PRGM, EXEC, INVF to load the program. It pastes prgmINVF on the home screen. ENTER to
execute your program.
You should see the AREA RIGHT: prompt.
Test it by entering
AREA RIGHT = .05
D1 = 13
D2 = 11
It may take several seconds to solve.
Check answer: F critical = 2.761417
Press ENTER again to solve for another F critical value.
Reload the program any time by going to PRGM, EXEC, ENTER.
If this was helpful, let people know with a thumbs up.
Tips as you’re building the program:
Command lines are automatically preceded by a colon.
Each time you finish a line, ENTER to go to the next line.
If you get stuck somewhere, use 2nd MODE to get to the home screen, click PRGM, EDIT, and choose your program to continue editing. All work is automatically saved.
When done, ENTER at the end of your last line. Press 2nd MODE to go to home screen.
Find Input and Disp in PRGM, I/O.
Find Solve( (TI-83) or Solver (TI-84) in MATH. Up arrow takes you to the bottom of the list.
Find fcdf( in 2nd VARS.
