Variability

Distributions of Normal
and Binomial Populations


The Standard Normal Distribution


Distribution of Standardized Normal Scores
Mean=0 Median=0 StDv= 1.00
This population is normal.


Binomial Distribution - N=4, P=Q=.5


Distribution of Binomial Scores for 4 coin tosses
Mean=2 Median=2
This population is not normal at all.


Binomial Distribution - N=6, P=Q=.5


Distribution of Binomial Scores for 6 coin tosses
Mean=3 Median=3
This population is a bit closer to normal.


Binomial Distribution - N=10, P=Q=.5


Distribution of Binomial Scores for 10 coin tosses
Mean=5 Median=5
This population is closer to normal.


Binomial Distribution - N=30, P=Q=.5


Distribution of Binomial Scores for 30 coin tosses
Mean=15 Median=15 StDv=2.7386
This population is very close to normal.
The StDv value is the normal approximation.