Box plots and identification of outliers
A box plot is a simple chart used to summarize the distribution of a dataset. It shows the minimum, maximum, median, quartiles, and spread of the data, making patterns and outliers easy to identify.
The box represents the middle 50% of the data (from Q1 to Q3), with a line showing the median. Whiskers extend to the minimum and maximum values, excluding outliers. Points outside the whiskers are called outliers.
Outliers are important because they can affect statistical results, influence model performance, or highlight unusual but meaningful events. They should be handled by checking their cause, using statistical methods to evaluate them, or applying models that are less sensitive to extreme values.
Interquartile Range (IQR) is calculated as: IQR = Q3 - Q1
An outlier is any data point that lies outside the bounds defined by:
Lower Bound= q1-1.5 * IQR
Upper Bound= q3 +1.5 * IQR
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