When we have a bunch of data, we must organize and visualize it in order to make sense of it. Hans Rosling, a Swedish doctor, mathematician, and professor, has a great video showing one of the earliest methods used to visualize data.
A standard way to visualize categorical data is by finding the frequency of different occurrences. For example, let’s say we have a random sample of 50 statistics students and the country in which they live.
(first six rows)
In this spreadsheet, each row represents one student (except Row 1, which is the header). For example, the student represented by Row 2 is from the United States.
If we want to know the most common country in which statistics students live, we should make a frequency table by counting the number of occurrences of each country, e.g.
We can do this manually, or use a statistical program. Let’s see how it’s done using R.
Continue to Lesson 3, or select a lesson below.
Lesson 1: Introduction to Statistical Research Methods
Lesson 2: Visualizing Data
Lesson 3: Central Tendency
Lesson 4: Variability
Lesson 5: Standardizing
Lesson 6: Normal Distribution
Lesson 7: Sampling Distributions
Lesson 8: Estimation
Lesson 9: Hypothesis Testing
Lesson 10: t-Tests for Dependent Samples
Lesson 11: t-Tests for Independent Samples
Lesson 12: Intro to One-Way ANOVA
Lesson 13: One-Way ANOVA: Test significance of differences
Lesson 14: Correlation
Lesson 15: Linear Regression
Lesson 16: Chi-Squared Tests