Provide at least three ways to detect outliers in a dataset?

1.	Provide at least three ways to detect outliers in a dataset?
Answer» There are various methods. The most COMMON method is to use visualization using box-plots, HISTOGRAMS and scatter plots to detect outliers. Another way - Any VALUE, which is beyond the range of -1.5 x IQR to 1.5 x IQR (where IQR stands for Inter-Quartile Range). Use capping methods. Any value which out of range of 5th and 95th percentile can be considered an outlier. Others could be as follows: DATA points, three or more standard deviations away from the mean are considered as outlier.

Answer»

There are various methods.

The most COMMON method is to use visualization using box-plots, HISTOGRAMS and scatter plots to detect outliers.
Another way - Any VALUE, which is beyond the range of -1.5 x IQR to 1.5 x IQR (where IQR stands for Inter-Quartile Range).
Use capping methods. Any value which out of range of 5th and 95th percentile can be considered an outlier.

Others could be as follows: DATA points, three or more standard deviations away from the mean are considered as outlier.

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Provide at least three ways to detect outliers in a dataset?

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