IPS_chapter01.1

IPS_chapter01.1 - Looking at data: distributions -...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
    Looking at data: distributions Displaying distributions with graphs IPS chapter 1.1 © 2006 W.H. Freeman and Company Rev. 2006 T.F. Devlin
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Outline (Chapter 1.1) Introduction Looking at categorical variables Bar graphs Looking at quantitative variables Interpreting the graph Constructing the graph
Background image of page 2
Statistical Science Statistics is the Science of Data and Variability. What is Statistics? What is Data?
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Statistical Science Statistics is the science of data and variability. Data are not just numbers.
Background image of page 4
Statistical Science Statistics is the Science of Data and Variability. Data are numbers and values with a context . Who What Why Data are not just numbers .
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Statistical Science Statistics is the science of data. Data are not just numbers. Data are numbers and values with a context . Who, what, why Who are the objects described by the data? Individuals What are the characteristics of the individuals? Variables .
Background image of page 6
Variables In a study, we collect information—data—from individuals . Individuals can be people, animals, plants, or any object of interest. A variable is a characteristic that varies among individuals in a population or in a sample (a subset of a population). Example: age, height, blood pressure, ethnicity, leaf length, first language The distribution of a variable tells us what values the variable takes and how often it takes these values.
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Two types of variables Variables can be either quantitative… Something that can be counted or measured for each individual and then added, subtracted, averaged, etc. across individuals in the population. Example: How tall you are, your age, your blood cholesterol level, the number of credit cards you own … or categorical. Something that falls into one of several categories. What can be counted is the count or proportion of individuals in each category. Example: Your blood type (A, B, AB, O), your hair color, your ethnicity, whether you paid income tax last tax year or not
Background image of page 8
How do you know if a variable is categorical or quantitative? Ask:
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 29

IPS_chapter01.1 - Looking at data: distributions -...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online