Skip to main content

Posts

Find-S Algorithm in Python

def find_s_algorithm ( data , target ):     # Step 1: Initialize the most specific hypothesis     hypothesis = [ "Φ" ] * len (data[ 0 ])     # Step 2: Iterate over the dataset     for i, instance in enumerate (data):         if target[i] == "Yes" :   # Process only positive examples             for j in range ( len (instance)):                 if hypothesis[j] == "Φ" :   # Initialize to the first positive example                     hypothesis[j] = instance[j]                 elif hypothesis[j] != instance[j]:   # Generalize if there's a mismatch                     hypothesis[j] = "?"         return hypothesis # Example Dataset attributes = [     [ "Sunny" , "Warm" , ...

ML Lab Questions

1. Using matplotlib and seaborn to perform data visualization on the standard dataset a. Perform the preprocessing b. Print the no of rows and columns c. Plot box plot d. Heat map e. Scatter plot f. Bubble chart g. Area chart 2. Build a Linear Regression model using Gradient Descent methods in Python for a wine data set 3. Build a Linear Regression model using an ordinary least-squared model in Python for a wine data set  4. Implement quadratic Regression for the wine dataset 5. Implement Logistic Regression for the wine data set 6. Implement classification using SVM for Iris Dataset 7. Implement Decision-tree learning for the Tip Dataset 8. Implement Bagging using Random Forests  9.  Implement K-means Clustering    10.  Implement DBSCAN clustering  11.  Implement the Gaussian Mixture Model  12. Solve the curse of Dimensionality by implementing the PCA algorithm on a high-dimensional 13. Comparison of Classification algorithms  14. Compa...

MCQ Questions

Machine Learning Quiz Machine Learning Quiz 1. What is supervised learning? A. Learning without labeled data B. Learning with labeled data C. A method to clean data D. None of the above 2. Which algorithm is used for classification problems? A. Linear Regression B. Logistic Regression C. K-Means Clustering D. Gradient Descent 3. What is overfitting in a machine learning model? A. The model performs well on training data but poorly on test data B. The model performs well on both training and test data C. The model does not learn anything D. None of the above...

Solve the curse of dimensionality by implementing the PCA algorithm on a high-dimensional

import numpy as np import pandas as pd from sklearn.datasets import make_classification from sklearn.decomposition import PCA import matplotlib.pyplot as plt # Step 1: Generate a High-Dimensional Dataset # Create a synthetic dataset with 100 features X, y = make_classification(n_samples=500, n_features=100, n_informative=10, n_redundant=20, random_state=42) # Convert the data to a DataFrame for easy manipulation data = pd.DataFrame(X) print("Original Data Shape:", data.shape) # Step 2: Apply PCA for Dimensionality Reduction # Specify the number of components to retain (e.g., keep 2 components for visualization) pca = PCA(n_components=2) reduced_data = pca.fit_transform(data) # Check the shape of the reduced data print("Reduced Data Shape:", reduced_data.shape) # Step 3: Check Explained Variance # This shows how much variance is retained by the selected components explained_variance = pca.explained_variance_ratio_ print("\nExplained Variance by each principal co...

Principal Component Analysis

  Principal Component Analysis (PCA) is a dimensionality reduction technique that transforms high-dimensional data into a lower-dimensional form while preserving as much of the original data’s variance as possible. PCA achieves this by creating new, uncorrelated variables called principal components , which are linear combinations of the original variables. These principal components capture the directions of maximum variance in the data, with the first few components typically containing most of the information. How PCA Works Standardize the Data : Center and scale the data so that each feature has a mean of zero and a variance of one. This step ensures that features with larger scales don’t dominate the results. Compute the Covariance Matrix : Calculate the covariance matrix to understand how features vary with respect to each other. Calculate Eigenvalues and Eigenvectors : Determine the eigenvalues and eigenvectors of the covariance matrix. Eigenvectors define the directions (...

Curse of Dimensionality

 The curse of dimensionality refers to the various phenomena that arise when analyzing data in high-dimensional spaces that do not occur in low-dimensional settings. As the number of dimensions (features) in a dataset increases, several challenges emerge, often making analysis, machine learning, and statistical modeling difficult and inefficient. Here’s a breakdown of the key issues: 1. Sparsity of Data In high-dimensional spaces, data points become sparse. As dimensions increase, the volume of the space grows exponentially, and a fixed number of data points becomes sparse in this larger space. For example, if we were to add new features to a dataset with a fixed number of samples, the density of the samples in the feature space decreases, leading to sparse data and difficulty in finding meaningful patterns. 2. Distance Metrics Lose Meaning Many machine learning algorithms rely on distance metrics (e.g., Euclidean distance). In high dimensions, the distance between any two points ...

Gaussian Mixture Model

A Gaussian Mixture Model (GMM) is a probabilistic model used for clustering and density estimation. It assumes that data is generated from a mixture of several Gaussian distributions, each representing a cluster within the dataset. Unlike K-means, which assigns data points to the nearest cluster centroid deterministically, GMM considers each data point as belonging to each cluster with a certain probability, allowing for soft clustering. GMM is ideal when: Clusters have elliptical shapes or different spreads : GMM captures varying shapes and densities, unlike K-means, which assumes clusters are spherical. Soft clustering is preferred : If you want to know the probability of a data point belonging to each cluster (not a hard assignment). Data has overlapping clusters : GMM allows a point to belong partially to multiple clusters, which is helpful when clusters have significant overlap. Applications of GMM Image Segmentation : Used to segment images into regions, where each region can be...