Tuesday, October 23, 2012

Calculation of normal distribution in statistical calculation

Model : CASIO  fx-991MS, CASIO fx-570MS, CASIO  fx-100MS

In statistics often it is necessary to calculate normal distribution.Normal distribution indicates percentage of chance of occurrence of an event based on the observed data.It's one type of probability distribution.

Example: Calculate normalized variate(→t) for x=53 and normal probability distribution P(t) for the following data 55,54,51,55,53,53,54,52.Also calculate Q(t) and R(t) for these data.(Ans: -0.28, 0.387, 0.112, 0.612 respectively)



Solution:

(Mode initialization)
MODE >> MODE >> 1(SD)

(Clear memory Important, any previous statistical calculation data interfere with present calculation resulting error if this step is not followed. So before starting every statistical calculation statistical memory must be cleared)
SHIFT >> MODE >> 1(Scl) >> = (Stat clear)

(Input data)
5 >> 5 >> M+(n=1) >> 5 >> 4 >> M+(n=2) >> 5 >> 1 >> M+(n=3) >> 5 >> 5 >> M+(n=4) >> 5 >> 3 >> M+(n=5) >> 5 >> 3 >> M+(n=6) >> 5 >> 4 >> M+(n=7) >> 5 >> 2 >> M+(n=8)

(Calcuation of normalized variate →t for x=53)
5 >> 3 >> SHIFT >> 3 >> 4(53→t) >> =

(Calcuation of probability distribution P( , Q( , R(  for x=53)
SHIFT >> 3 ( P( ) >> 1 >> >> . >> 2 >> 8 >> ) >> = (here previously determined normalized variate (in this case -0.28) is to be used to calculate distribution for x=53)

SHIFT >> 3 ( Q( ) >> 2 >> >> . >> 2 >> 8 >> ) >> = (here previously determined normalized variate (in this case -0.28) is to be used to calculate distribution for x=53)

SHIFT >> 3 ( R( ) >> 3 >> >> . >> 2 >> 8 >> ) >> = (here previously determined normalized variate (in this case -0.28) is to be used to calculate distribution for x=53)

The same procedure is followed to determine probability distribution of two variables related with a function (Ex: y=ax+b) in REG MODE.