An outlier is any value that is numerically faraway from most of the other data points in a set of data. And an outlier is not uncommon to find an outlier in a data set.
I) In statistics, an outlier is an observation point that is faraway from remaining observations.
II) An outlier may be due to lack of consistency in the measurement
III) It may be cause serious problems in statistical analysis and can occur in any distribution.
Outliers can have many causes such as:
A)Measurement or input error
C)Outlier values, possibly in the context of non – outlier values to see if there are systematic relationship.
Two activities are essential for characterizing a set of data:
1. Overall shape of the graphed data for important features, including coordination and departure from acceptance.
2.The data for different examination that are far removed from the mass of data. Here two graphical techniques for identifying outliers, scatter plots and box plots, along with an analytic procedure for detecting