# Sec 1.1 Descriptive and Inferential Statistics

```Chapter 1
The Nature of Probability
and Statistics
Chapter 1 Overview
Introduction
1-1 Descriptive and Inferential Statistics
1-2 Variables and Types of Data
1-3 Data Collection &amp; Sampling Techniques
1-4 Observational and Experimental Studies
1-5 Uses and Misuses of Statistics
1-6 Computers and Calculators
Bluman Chapter 1
2
Introduction

Statistics is the science of conducting
studies to
collect,
organize,
summarize,
analyze, and
draw conclusions from data.
Bluman Chapter 1
3
Section 1-1
Inferential and
Descriptive Statistics
Objective 1: knowledge of
statistical terms
 A variable is a characteristic or attribute
that can assume different values.
 The values that a variable can assume are
called data.
 Random variable: Any variable whose
value is determined by chance.
Objective 1: knowledge of
statistical terms
 A collection of data values forms a data
set.
 Each value in the data set is called a data
value or datum.
Objective 2: Two Branches of Statistics
Statistics
Descriptive
Statistics
Inferential
Statistics
Objective 2: Two Branches of Statistics
Statistics
Descriptive Statistics
consists of:
the collection,
organization,
summarization, and
presentation of data.
Inferential Statistics consists of:
1. generalizing from samples to
populations
2. performing estimations and
hypothesis tests.
3. determining relationships
among variables
4. making predictions.
More terms to know
 A Population consists of all subjects (
human or otherwise) that are being studied.
 A Sample is a group of subjects from a
population.