How many components are relevant?
The results that you stored in pcaNews
contain as many components as variables. But your goal is a dimension reduction. It's time to find out how many components you should extract. Use several approaches to make your decision.
The results of the pca pcaNews
are still loaded in your workspace. All necessary packages are loaded.
Diese Übung ist Teil des Kurses
Machine Learning for Marketing Analytics in R
Anleitung zur Übung
- Create a screeplot. How many components does it suggest?
- How many components would you need to meet the criterion of 70% variance explained (take a look at the
summary()
)? - How many components would you extract according to the Kaiser-Guttmann criterion?
Interaktive Übung
Vervollständige den Beispielcode, um diese Übung erfolgreich abzuschließen.
# Screeplot:
___(___, type = ___)
# Cumulative explained variance:
___(___)
# Kaiser-Guttmann (number of components with eigenvalue larger than 1):
sum(pcaNews$___ > ___)