What
is Statistics
Course
Documentation
CJ
Alverson
What
is Statistics ? Stated informally,
Statistics is the process of
describing characteristics of a sample of objects of interest. Statistics
has two basic levels of activity - descriptive and inferential.
Descriptive statistics is concerned with describing the sample.
Inferential statistics is concerned with checking the plausibility of
specific hypotheses against a sample.
Typically,
applications of modern statistics involve both descriptive and inferential
statistical methods.
The formal tools
used in both types of Statistics come from Probability.
What
is Probability ? Stated informally,
Probability is the branch of Mathematics
concerned with modeling the likelihood of the occurrence of events. Probability
models describe the likelihood of specific events associated with
specific processes.
For example, a
simple probability model applies to the tosses of a coin. The starting point of
this probability model is given by the likelihood that a particular face of the
coin will show on a single toss.
Descriptive
statistics typically involves the estimation of probability models
from samples.
Inferential
statistics typically involves checking a sample against a specific
probability model.
First
we will learn something about Probability, and then we will learn something
about Statistics.