Sage-Tips

How does logistic regression compare to Knn?

KNN is comparatively slower than Logistic Regression. KNN supports non-linear solutions where LR supports only linear solutions. LR can derive confidence level (about its prediction), whereas KNN can only output the labels.

What is the advantage of the K nearest neighbors method?

It stores the training dataset and learns from it only at the time of making real time predictions. This makes the KNN algorithm much faster than other algorithms that require training e.g. SVM, Linear Regression etc.

What are the advantages of using KNN K Nearest Neighbor algorithms?

Some Advantages of KNN

• Quick calculation time.
• Simple algorithm – to interpret.
• Versatile – useful for regression and classification.
• High accuracy – you do not need to compare with better-supervised learning models.

What is the difference between K means support vectors machine and KNN algorithms?

K-means is an unsupervised learning algorithm used for clustering problem whereas KNN is a supervised learning algorithm used for classification and regression problem. This is the basic difference between K-means and KNN algorithm. It makes predictions by learning from the past available data.

When do you use logistic vs linear regression?

Linear regression is used for predicting the continuous dependent variable using a given set of independent features whereas Logistic Regression is used to predict the categorical. Linear regression is used to solve regression problems whereas logistic regression is used to solve classification problems.

What are the strengths and weaknesses of K NN algorithm?

Strength and Weakness of K Nearest Neighbor

• Robust to noisy training data (especially if we use inverse square of weighted distance as the “distance”)
• Effective if the training data is large.

What are the strengths and weaknesses of KNN algorithm?

What are different similarities between K-means and KNN?

How is the K-nearest neighbor algorithm different from K-means clustering? KNN Algorithm is based on feature similarity and K-means refers to the division of objects into clusters (such that each object is in exactly one cluster, not several). KNN is a classification technique and K-means is a clustering technique.

How do we decide the value of k in KNN and K-means algorithm?

The optimal K value usually found is the square root of N, where N is the total number of samples. Use an error plot or accuracy plot to find the most favorable K value. KNN performs well with multi-label classes, but you must be aware of the outliers.

What is the difference between k-nearest neighbors and logistic regression?

Logistic regression requires some training. Decision boundary: Logistic regression learns a linear classifier, while k-nearest neighbors can learn non-linear boundaries as well. Predicted values: Logistic regression predicts probabilities, while k-nearest neighbors predicts just the labels.

What is the advantage of logistic regression over regular regression?

Logistic regression is easier to implement, interpret, and very efficient to train. If the number of observations is lesser than the number of features, Logistic Regression should not be used, otherwise, it may lead to overfitting. It makes no assumptions about distributions of classes in feature space.

Is linearly separable data useful in logistic regression?

Linearly separable data is rarely found in real-world scenarios. Good accuracy for many simple data sets and it performs well when the dataset is linearly separable. Logistic Regression requires average or no multicollinearity between independent variables. It can interpret model coefficients as indicators of feature importance.

Does logistic regression require multicollinearity?

Logistic Regression requires moderate or no multicollinearity between independent variables. This means if two independent variables have a high correlation, only one of them should be used. Repetition of information could lead to wrong training of parameters (weights) during minimizing the cost function.