Lecture Notes Chapter 1: Introduction to Statistics.
The term Statistics originally referred to " affairs of the state" (think "state-
is-tics"), such as the number of people in a kingdom or the amount of tax revenue
collected. A more modern definition of the term statistics would be "data-o-logy"-
so you should think of statistics as the science of data.
What is Statistics? Statistics is the art and science of collecting, organizing,
analyzing, and interpreting data in order to make decisions.
Data consist of information coming from observations, counts, measurements, or
responses.
Data can be numerical, as in height, or they can be nonnumerical, as in gender. In
either case, data describe characteristics of an individual.
Quantitative data consist of numerical measurements or counts.
Qualitative data consist of attributes, labels, or nonnumeric entries.
There are two branches of Statistics: (Descriptive Statistics and Inferential
Statistics)
Descriptive Statistics: (The Building Blocks of Data Analysis)
As a first step in data analysis, we use numbers (such as counts and percents) and
graphics to describe the data set.
Suppose we are collecting data about the patients in a particular hospital,
including the diagnosis, length of stay, gender, and total cost. The sources of the
information (the patients) are called the elements. the patients' characteristic (for
