In this article, we’ll unpack all you need to know about the Bell Curve, defining exactly what it is, its parameters, its benefits, its limitations and more.
What Is The Bell Curve?
The Bell Curve (BC), also referred to as the Normal Distribution or the Gaussian Distribution, is a statistical graph that is used to represent the distribution of data.
The BC is characterised by a symmetrical curve that has a peak in the middle and tails that taper off on either side. The highest point (the top of the “bell”) represents the most probable event in a series of data while all other outcomes are symmetrically distributed around it.
The Parameters
The Bell Curve is defined by its mean, median, mode and standard deviation.
For a perfectly normal distribution, the mean, median and mode will all be the same value, visually represented by the peak of the curve. The standard deviation depicts the BC’s relative width around the mean.
The Bell Curve & Standard Deviation
Standard deviation refers to how spread out the data is. In other words, it is a measure of how far each observed value is from the mean.
In any distribution, about 95% of values will be within two standard deviations of the mean.
The Benefits
The Bell Curve allows us to make statistical inferences and predictions about the future.
For example, we know that approximately 68% of data falls within one standard deviation of the mean. 95% of data falls within within two standard deviations of the mean. 99.7% of data falls within within three standard deviations of the mean.
Thus, understanding this statistical tool can allow us to unlock a deeper comprehension of data and its potential applications.
The Limitations
The Bell Curve is not always the best tool for statistical analysis because not all data is normally distributed.
For example, data that is skewed or has outliers will not fit well with a BC. In such cases, other distributions may therefore be more appropriate.
Summary (TL;DR)
The Bell Curve is a type of statistical graph that is used to visualize the distribution of data. It tends to have central normal values as peak with low and high extremes tapering off symmetrically on either side.
The mean, median and mode of a perfectly distributed BC are all the same. The standard deviation determines how wide the curve is.
The BC can be a useful tool for analysing and interpreting data and making informed predictions about the future. However, it is important to remember its limitations.
