what does normal distribution mean in psychology
The standard normal distribution is the normal distribution with a mean of zero and a standard deviation of one (the green curves in the plots to the right). It is often called the bell curve because the graph of its probability density resembles a bell.ome notable qualities of the normal distribution: 1  The density function is symmetric about its mean value. 2  The mean is also its mode and median. 3  68.268949% of the area under the curve is within one standard deviation of the mean.