DA0-002 Data Analysis Practice Question
A data scientist is building a K-means clustering model for customer segmentation. After plotting the within-cluster sum of squares (WCSS) against the number of clusters (k), she observes that the WCSS decreases sharply until k=5 and then levels off. Which value of k should she choose based on the elbow method?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
k=5
The elbow method suggests selecting the number of clusters at the point where the WCSS starts to diminish less rapidly, forming an 'elbow'. Here, the elbow is at k=5, where adding more clusters yields diminishing returns.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
k=5
Why this is correct
Correct elbow point.
- ✗
k=6
Why it's wrong here
After the elbow, gains are minimal.
- ✗
k=4
Why it's wrong here
The elbow is at k=5.
- ✗
k=3
Why it's wrong here
The elbow is at k=5, not 3.
Go deeper
Related to this question
About these practice questions
One of 986 original DA0-002 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DA0-002 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DA0-002 exam.