Summarize · Week 05
Descriptive Statistics
Interpret center and spread, compare distributions with quartiles and boxplots, and practice filtering values from vectors.
Sep 21–25Lecture 4 + Classwork 3Classwork 4 + Homework 1
ImportantWeek 5 sequence
- Use Lecture 4 to study measures of center and spread, quartiles, and boxplots.
- Use Classwork 3 to calculate and interpret descriptive statistics in R.
- Practice keeping vector values by position or condition in Classwork 4, and complete Homework 1.
Focus
- Center, spread, quartiles, IQR, and boxplots
- Subsetting by position and filtering by condition
- Interpreting summaries in context
Prepare
- Open Lecture 4 and Classwork 3
- Bring your R script and section project
- Have Classwork 4 and Homework 1 ready
Practice
- Calculate and interpret descriptive statistics
- Keep vector values by position or logical condition
- Explain what quartiles and a boxplot reveal
Learning targets
- Interpret measures of center and spread in context.
- Calculate and explain range, variance, standard deviation, quartiles, and IQR.
- Read a boxplot using its median, quartiles, spread, and possible outliers.
- Subset vector values by position and filter them by logical condition.
- Explain that filtering keeps values that satisfy the filtering rule and omits the others.
Core pattern
scores <- c(72, 85, 79, 91, 88)
mean(scores)
median(scores)
sd(scores)
quantile(scores)
IQR(scores)Lecture slides
TipLecture slide shortcuts
Click inside the slide preview, then use:
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- F to enter fullscreen;
- E to enter or exit PDF export mode;
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