GDB STA301 ( Statistics and Probability) Fall 2011

http://vulms.vu.edu.pkThe normal distribution was discovered in 1733. The normal distribution has a bell-shaped curve.  Large number of results involving this distribution can be derived in explicit from and it (normal distribution) arises as the outcome of the central limit theorem. A symmetrical distribution is commonly shaped like a bell curve when depicted on a graph. If a line is drawn down the middle of the graph then two sides will be mirror of each other. Symmetrical and Normal Distributions are U – Shaped and are equal from both sides.

The normal distributions are a very important class of statistical distributions. All normal distributions are symmetric and have bell- shaped density curves with a single peak. Both the normal and symmetrical distributions are u-shape and equal from both sides. Thus not all symmetric distributions are normal