Ask Ghassem - Recent questions tagged naive-bayes

How to calculate the class probabilities and classify using Naive Bayes classifier?

Mon, 10 Aug 2020 21:26:28 +0000

We have data on 1000 pieces of fruit. The fruit being a Banana, Orange or some Other fruit and imagine we know 3 features of each fruit, whether it’s long or not, sweet or not and yellow or not, as displayed in the table below:

https://i.imgur.com/gOFzVXL.png

A piece of an unknown fruit with these features are provided: Long, Sweet and Yellow.

Calculate probability of each of these 3 classes based on Naive Bayes Classification algorithm and report the class.

How to calculate the class probabilities and classify using Naive Bayes classifier for NLP?

Wed, 26 Jun 2019 19:43:41 +0000

We want to use Naive Bayes for tagging documents. It is a classification task that we want to assign a class (tag) to each string. We currently have two tags: Sport and Not Sport

Which tag does the sentence A very close game belong to? Using Naive Bayes classifier, calculate the class probability for Sport and Not sport for this sentence based on the dataset and decide about the tag.

Text	Tag
“A great game”	Sports
“The election was over”	Not sports
“Very clean match”	Sports
“A clean but forgettable game”	Sports
“It was a close election”	Not sports

Is Naive Bayes a good classifier?

Thu, 04 Oct 2018 00:23:00 +0000

Here is an example of training a model using the Naïve Bayes classifier on the Glass dataset(from UCI). The objective is to predict the type of glass based on the 9 parameters. The metric used to understand the classification result are confusion matrix and classification report.

The program is available here

Few Observations/ Questions

By Varying the ‘random_state’ value inside the function train_test_split, we can observe different accuracy values? Is the behavior correct?
The StratfiedShuffle method of train_test_split also produces random results on the every run. Is there a bug with Naïve Bayes classifier implementation?

What is Bayes’ Theorem? How is it useful in machine learning? Where should we use it?

Thu, 27 Sep 2018 05:27:55 +0000