The Nature of Statistics
Statistics is the science of collecting, organizing,
summarizing, and analyzing information to draw conclusions or answer
questions. In addition, statistics is about providing a measure of
confidence in any conclusions.
The Process of Statistics
- Identify the research objective
- Collect the data
- Describe the data
- Perform inference
Example What percentage of Mercer
University students are residents of Georgia?
Example How many hours per day do Mercer
University students sleep?
\(\ominus\) Key terms:
population
vs. sample
parameter
vs. statistic
descriptive statistics
vs. inferential statistics
Classroom Activity Do you think true/false
quizzes effectively assess student’s leanring outcome? (e.g., How likely
can a student pass the quiz by guessing all the answers?) Take a 10 question
true/false quiz. What does the data suggest?
Classroom Activity How about
multiple-choice quizzes? Take another quiz with 10 multiple-choice questions. This
time, what does the data suggest?
Variables
A data frame is a table in which each row represents
an individual and each column represents a variable measured on the
individuals.
Example A mock dataset with fictional
credit information.
df <- read.csv("https://albums.yuanting.lu/sta126/data/credit.csv")
\(\ominus\) Key terms:
qualitative/categorical variables
vs. quantitative/numerical variables
discrete numerical variables
vs. continuous numerical variables