K means clustering Study guides, Class notes & Summaries

The correct number of clusters in Hierarchical clustering can be determined precisely using approaches such as silhouette scores (True or False) - correct answer False In K Means clustering, the analyst does not need to determine the number of clusters (K), these are always derived analytically using the kmeans algorithm. (True or False) - correct answer False One big difference between the unsupervised approaches in this module, and the supervised approaches in prior modules: Unsupervised...

This document contains a summary of all datacamp modules with all important codes, functions, methods and steps to perform certain analysis. Useful for pacticing before the exam.

ISYE6501: MIDTERM 1 LATEST 2023 RATED A Matching models/methods to categories (cusum and pca = NONE) Select all of the following models that are designed for use with attribute/feature data (i.e., not time-series data): k-nearest-neighbor, PCA, k-means, logistic regression, linear regression, random forest, SVM's Classification models CART, k-nearest-neighbor, logistic regression, random forest, support vector machine Clustering k-means Response prediction ARIMA, Exponential smoothing, Lin...

What do descriptive questions ask? What happened? (e.g., which customers are most alike) What do predictive questions ask? What will happen? (e.g., what will Google's stock price be?) What do prescriptive questions ask? What action(s) would be best? (e.g., where to put traffic lights) What is a model? Real-life situation expressed as math. What do classifiers help you do? differentiate What is a soft classifier and when is it used? In some cases, ther...

ISYE-6501 Exam 1 QUESTIONS & CORRECT ANSWERS Algorithm - ANSWER a step-by-step procedure designed to carry out a task Change Detection - ANSWER Identifying when a significant change has taken place Classification - ANSWER Separation of data into two or more categories Classifier - ANSWER A boundary that separates data into two or more categories Cluster - ANSWER A group of points that are identified as being similar or near each other Cluster Center - ANSWER In some clustering ...

ISYE 6501 Final Questions and Answers Already Passed Support Vector Machine A supervised learning, classification model. Uses extremes, or identified points in the data from which margin vectors are placed against. The hyperplane between these vectors is the classifier SVM Pros/Cons Pros: It works really well with a clear margin of separation It is effective in high dimensional spaces. It is effective in cases where the number of dimensions is greater than the number of samples. It uses a subse...

ISYE-6501 Exam 1 QUESTIONS & CORRECT ANSWERS Algorithm - ANSWER a step-by-step procedure designed to carry out a task Change Detection - ANSWER Identifying when a significant change has taken place Classification - ANSWER Separation of data into two or more categories Classifier - ANSWER A boundary that separates data into two or more categories Cluster - ANSWER A group of points that are identified as being similar or near each other Cluster Center - ANSWER In some clustering ...

Data Science 11 - Clustering algorithms k-Means and variants; Initialization: • Randomly chooses k points from X used as the initial means • k-Means++: Pick initial means, such that they are uniformly distributed in the space. This leads to faster convergence k-Means and variants; Representatives: • k-Medoids or Partitioning Around Medoids (PAM): The cluster representatives are medoids (objects from X). Only the distance between objects is needed Problems with k-Means: • Cluste...

Rows Data points are values in data tables Columns The 'answer' for each data point (response/outcome) Structured Data Quantitative, Categorical, Binary, Unrelated, Time Series Unstructured Data Text Support Vector Model Supervised machine learning algorithm used for both classification and regression challenges. Mostly used in classification problems by plotting each data item as a point in n-dimensional space (n is the number of features you have) with ...

ISYE-6501 Exam 1 QUESTIONS & CORRECT ANSWERS Algorithm - ANSWER a step-by-step procedure designed to carry out a task Change Detection - ANSWER Identifying when a significant change has taken place Classification - ANSWER Separation of data into two or more categories Classifier - ANSWER A boundary that separates data into two or more categories Cluster - ANSWER A group of points that are identified as being similar or near each other Cluster Center - ANSWER In some clustering ...