
Scala for Machine Learning, Second Edition
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Real-world observations are usually noisy and inconsistent, with missing data. No classification, regression, or clustering model can extract reliable information from data that has not been cleansed, filtered, or analyzed.
Data preprocessing consists of cleaning, filtering, transforming, and normalizing raw observations using statistics in order to correlate features or groups of features, identify trends, model, and filter out noise. The purpose of cleansing raw data is twofold:
You should not underestimate the power of traditional statistical analysis methods to infer and classify information from textual or unstructured data.
In this chapter, you will learn how to to the following: