New to tidyverse? This short primer covers installation, the pipe operator (|>), and how tidyverse code compares to the base R you learned in Swirl. Read this before the exercises below.

Step through the six-stage Korean text preprocessing pipeline on real presidential speech sentences. Toggle POS tags and stopwords to see how filtering choices shape the final output.

Word clouds, frequency analysis, and concordance using the NIKH history textbook corpus. Compare how language differs across colonial, authoritarian, and democratic eras — with optional R code you can expand and run yourself.

Hierarchical clustering on TF-IDF vectors from 11 NIKH textbooks. See a dendrogram, compare cluster assignments to era labels, and explore which words make each cluster distinctive.

K-means on 749 democratic-era speeches. Use silhouette scores to choose k, then discover whether clusters group by president or by topic — with a surprising result.