
Chapter 4
Maintaining Histograms from Data
Streams
Histograms are one of the most used tools in exploratory data analysis. They
present a graphical representation of data, providing useful information about
the distribution of a random variable. Histograms are widely used for density
estimation. They have been used in approximate query answering, in process-
ing massive datasets, to provide a quick but faster answer with error guaran-
tees. In this chapter we present representative algorithms to learn histograms
from data streams and its application in data mining.
4.1 Introduction
A histogram is visualized as a bar graph that shows frequency data. The ...