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Displaying the Order in a Group of Numbers Using Tables and Graphs. Chapter 1. https:// jasp-stats.org /2018/05/01/how-to-run- jasp -in-your-browser/. Chapter Outline. The Two Branches of Statistical Methods Some Basic Concepts Kinds of Variables Frequency Tables Histograms
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Displaying the Order in a Group of Numbers Using Tables and Graphs Chapter 1
https://jasp-stats.org/2018/05/01/how-to-run-jasp-in-your-browser/https://jasp-stats.org/2018/05/01/how-to-run-jasp-in-your-browser/
Chapter Outline • The Two Branches of Statistical Methods • Some Basic Concepts • Kinds of Variables • Frequency Tables • Histograms • Shapes of Frequency Distributions • Frequency Tables and Histograms in Research Articles
Why Learn Statistics? • Understand research articles • Help you on your own research • Improve your reasoning and intuition • Better consumer of science
What is Statistics? • A branch of mathematics focusing on the organization, analysis, and interpretation of a group of numbers • Two Main Branches of Statistics • descriptive statistics: • used to summarize and describe a group of numbers from a research study • inferential statistics: • procedures for drawing conclusions based on the scores collected in a research study but going beyond them
EXCELLENT ECONOMY BAD ECONOMY 100 Abortions 0 Abortions
Basic Concepts • Variable • characteristic or condition that can have different values • e.g., level of stress • Value • possible number or category a score can have • e.g., 0–10 • Score • particular person’s value • e.g., a study participant rates her current level of stress as a 5 on a scale of 0–10
Kinds of Variables • Numeric Variable • variable that has values that are numbers • Age, height, salary • Nominal Variable • variable that has values that are names or categories (Eye Color, Ethnicity)
Scales of Measurement • Nominal: variable in which values are categories (e.g., gender, religion, ethnicity) • Ordinal (Rank-order): numeric values correspond to the relative position of things measured (e.g., class rank birth order)
Scales of Measurement • Underlying numerical information provided by a measure • Equal-interval: Numeric Variable (No absolute ZERO) • Carries identity: Days with different temps receive different scores on scale • Magnitude: (cooler days receive lower scores) • Equal unit size: differences between values correspond to differences in the underlying thing being measured (Diff. between 20o & 40o is equivalent to the difference of 50o & 70o) • Units of measurement (intervals) between the numbers on the scale are all equal in size. • e.g., pain level, stress level, ratings of mood, age
How Are You Doing? • You are conducting a study to evaluate how happy students are when taking a statistics test. • For this study, you ask college students to rate their level of happiness on a scale of 0–10. • What is your variable of interest? • Is your variable • numeric • nominal • What level of measurement are you using? • equal-interval • numeric • nominal
Key Points • Descriptive statistics are used to describe and summarize a group of numbers from a research study. • A value is a number or category; a variable is a characteristic that can have different values; a score is a particular person’s value on the variable. • Some numeric variables are rank-ordered and some variables are names or categories and not numbers.