AWS Certified Cloud Practitioner

Explanation

Correct Answer: A. K-nearest neighbors (k-NN)

Why k-NN is correct:

1. Classification Problem: The task involves predicting flower classification (categorical outcome) based on multiple features (petal length, petal width, sepal length, sepal width).
2. k-NN for Classification: K-nearest neighbors is a supervised machine learning algorithm specifically designed for classification tasks where it classifies data points based on the majority class among their k-nearest neighbors in the feature space.
3. Multi-feature Support: k-NN works well with multiple input features like the four measurements mentioned.

Why other options are incorrect:

• B. K-mean: This is an unsupervised clustering algorithm, not a classification algorithm. It groups similar data points without using labeled training data.
• C. Autoregressive Integrated Moving Average (ARIMA): This is a time series forecasting algorithm used for predicting future values based on past values, not for classification tasks.
• D. Linear regression: This is used for predicting continuous numerical values, not categorical classifications. While logistic regression (a variant) could be used for classification, linear regression itself is not appropriate for classification problems.

Key Concepts:

• Classification vs. Regression: Classification predicts categorical labels, while regression predicts continuous values.
• Supervised vs. Unsupervised: k-NN is supervised (requires labeled training data), while k-means is unsupervised.
• Feature-based Classification: k-NN uses distance metrics in feature space to determine classification based on proximity to labeled examples.