Answer to Question #179666 in Statistics and Probability for Fiza manzoor

Question

The majority of the data is normally distributed if there are enough subjects. For instance, if you collected test scores of only a few honor students, the data will most likely not be normally distributed because you would have a sample that did not represent the entire population. But the identical test scores (for honor students) collected from all schools in a state will result in a normal distribution.

Identify an example of a population that you would expect to be normally distributed. Explain why you believe it would be normally distributed. Then, describe a subset of the population you identified and explain why it would not be normally distributed and what the distribution would look like.

Answer 1

Many things closely follow a Normal Distribution:

- heights of people

- size of things produced by machines

- errors in measurements

- blood pressure

- marks on a test

A normal distribution is a very important statistical data distribution pattern occurring in many natural phenomena, such as height, blood pressure, lengths of objects produced by machines, etc. Certain data, when graphed as a histogram (data on the horizontal axis, amount of data on the vertical axis), creates a bell-shaped curve known as a normal curve, or normal distribution.

Normal distributions are symmetrical with a T-single central peak at the mean (average) of the data. The shape of the curve is described as bell-shaped with the graph falling off evenly on either side of the mean. Fifty percent of the distribution lies to the left of the mean and fifty percent lies to the right of the mean.

The spread of a normal distribution is controlled by the standard deviation, The smaller the standard deviation the more concentrated the data.

The mean and the median are the same in a normal distribution.