CI95 ( AllData )

CONFIDENCE INTERVAL CALCULATION (95%) = IC95

Be the first to rate this function Log in to vote

Paolo Marchetto - Show more from this author
No one
http://paolomarchetto.it

Sample input:

PAS = 100, 102, 105, 99, 101, 105, 107, 112, 131, 92, 124

Sample output:

CI95% = 99.4-114.7

Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

/*
CONFIDENCE INTERVAL CALCULATION (95%) = CI95

CI95 (of an mean) = Mean( AllData )  +/-  t * STDerr

Where:

STDerr is the standard error;

The standard error of a mean is obtained by dividing the standard deviation by the square root of the sample's (AllData) numerosity (n).

AllData is the content of a multiple field or the content of a field read via a one-to-many relationship.

t is a coefficient derived from the "Table of t-values for Student's distribution" (here it's predetermined from a simplified table). You must take into account that the degrees of freedom in Italian 'Gradi Di Libertà' (GDL) are calculated as follow: AllData size - 1.
*/

Dichiara ( [
Mean = Media ( AllData );
STDerr =  DevSt ( AllData ) / RadiceQuad ( Conteggio ( AllData ) ) ;
GDL = Conteggio ( AllData )-1;
t = Casi ( GDL=1 ; 12,71 ; GDL=2 ; 4,303 ; GDL=3 ; 3,182 ; GDL=4 ; 2,776 ; GDL=5 ; 2,571 ; GDL=6 ; 2,447 ; GDL=7 ; 2,365 ; GDL=8 ; 2,306 ; GDL=9 ; 2,262 ; GDL=10 ; 2,228 ; GDL=11 ; 2,201 ; GDL=12 ; 2,179 ; GDL=13 ; 2,16 ; GDL=14 ; 2,145 ; GDL=15 ; 2,131 ; GDL=16 ; 2,12 ; GDL=17 ; 2,11 ; GDL=18 ; 2,101 ; GDL=19 ; 2,093 ; GDL=20 ; 2,086 ; GDL=21 ; 2,08 ; GDL=22 ; 2,074 ; GDL=23 ; 2,069 ; GDL=24 ; 2,064 ; GDL=25 ; 2,06 ; GDL=26 ; 2,056 ; GDL=27 ; 2,052 ; GDL=28 ; 2,048 ; GDL=29 ; 2,045 ; GDL=30 ; 2,042 ; GDL ≤ 35 ; 2,03 ; GDL ≤ 40 ; 2,021 ; GDL ≤ 40 ; 2,021 ; GDL ≤ 45 ; 2,014 ; GDL ≤ 50 ; 2,008 ; GDL ≤ 60 ; 2 ; GDL ≤ 70 ; 1,994 ; GDL ≤ 80 ; 1,989 ; GDL ≤ 90 ; 1,986 ; GDL ≤ 100 ; 1,982 ; GDL ≤ 120 ; 1,98 ; GDL ≤ 1000 ; 1,962 ; 1,96 );
LowerL = Arrotonda ( Mean - (t * STDerr) ; 2 );
UpperL = Arrotonda ( Mean + (t * STDerr) ; 2 )] ;
LowerL & " - "  &  UpperL)

CONFIDENCE INTERVAL CALCULATION (95%) = CI95

CI95 (of an mean) = Mean( AllData ) +/- t * STDerr

Where:

STDerr is the standard error;

The standard error of a mean is obtained by dividing the standard deviation by the square root of the sample's (AllData) numerosity (n).

AllData is the content of a multiple field or the content of a field read via a one-to-many relationship.

t is a coefficient derived from the "Table of t-values for Student's distribution" (here it's predetermined from a simplified table). You must take into account that the degrees of freedom in Italian 'Gradi Di Libertà' (GDL) are calculated as follow: AllData size - 1.

Comments

Note: these functions are not guaranteed or supported by BrianDunning.com. Please contact the individual developer with any questions or problems.

CI95 ( AllData )

Comments

Support this website.

Support this website.