2016-2017 Probability distributions

1.Discrete probability distributions are the binomial
distribution and Poisson distribution.
2. A continuous probability distribution is a probability
density function.  The area under the smooth curve is
equal to 1 and the frequency of occurrence of values
between any two points equals the total area under the
curve between the two points and the x-axis .
The normal distribution is the most important distribution in biostatistics.  It is frequently called the Gaussian distribution. It is used for continuous variables .
The two parameters of the normal distribution are the mean (µ) and the standard deviation (?).  The graph has a familiar bell-shaped curve.
It is symmetrical around the mean .2.  The mean, median and mode are all equal.3.  The total area under the curve above the x-axis is 1 square unit.  Therefore 50% is to the right of mean and 50% is to the left of mean.4.  Perpendiculars of:    ±1 (?) contain about 68%;     ±2 (?) contain about 95%;    ±3 (?) contain about 99.7%of the area under the curve.
A normal distribution is determined by  µ and ?.  The normal distribution creates a family of distributions depending on whatever the values of  µ and  ? are.  The most important member of that family is the standard normal distribution which has µ =0 and ? =1.