Skip to Main Content
SAS for R Users
book

SAS for R Users

by Ajay Ohri
September 2019
Beginner to intermediate content levelBeginner to intermediate
208 pages
3h 17m
English
Wiley
Content preview from SAS for R Users

11Statistics for Data Scientists

Data Scientists need to study statistics as well as computer science to be effective in their analytical journey.

11.1 Types of Variables

  1. QUANTITATIVE VARIABLES: Data that consists of counts or measurements. You can perform arithmetic operations on them. There are two types:
    1. Discrete Variable has a countable number of values within a specified range. For example, 14, 15, 17.
    2. Continuous Variable has an infinite number of values without any break or jump. For example, 14–16 (this includes 14.001 and also 14.0000001).
  2. CATEGORICAL VARIABLES: Variables that denote groupings or labels. Arithmetic operations cannot be performed on them.
    1. Nominal Variable has no ordering within its observed levels, groups, or categories. For example, gender (male and female cannot be ordered).
    2. Ordinal Variable has meaningful ordering within its levels. For example, Disease condition divided into categories of low, moderate, or severe.
Tree diagram displaying “Variable” branching to “Numeric” and “Categorical,” with “Numeric” branching to “Continuous” and “Discrete” and “Categorical” branching to “Ordinal” and “Nominal.”

Figure 11.1 Variable types.

11.2 Statistical Methods for Data Analysis

Two main statistical methods are used in data analysis: descriptive statistics, which summarize data from a sample using indexes such as the mean or standard deviation, and inferential statistics, which draw conclusions from data that are subject to random variation (e.g. observational errors, sampling variation)

Descriptive statistics Inferential statistics ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

Statistical Hypothesis Testing with SAS and R

Statistical Hypothesis Testing with SAS and R

Sonja Kuhnt, Dirk Taeger

Publisher Resources

ISBN: 9781119256410Purchase book