Questions tagged [naive-bayes]

A naive Bayes classifier is a simple probabilistic classifier based on applying Bayes' theorem with strong independence assumptions. A more descriptive term for the underlying probability model would be "independent feature model".

567 questions
Filter by
Sorted by
Tagged with
36 views

Need suggestion/guide on how to estimate unknown bayesian priors

Suppose I can only observe people who visit Starbucks. My posterior probabilities will be like $\Pr(\text{male} \mid \text{visits Starbucks})$, $\Pr(\text{has hair} \mid \text{visits Starbucks})$, ...
278 views

I'm trying to do text detection thanks to Naive Bayes Algorithm. If I teach my tool: "Football is a great hobby" and assign it to the label "football", I'm totally fine with it detecting "I play ...
3k views

Confused among Gaussian, Multinomial and Binomial Naive Bayes for Text Classification

I am doing text classification but I am confused which Naive Bayes model I should use. What I understood by reading answers from couple of places that Gaussian Naive Bayes can be used if the attribute ...
51 views

Can inferencing come from incomplete rule sets?

I have some data for medical diagnosis, consisting of some rules about relationship of diseases and their symptoms, for example disease D1 frequently has symptom S1 ...
2k views

Naive Bayes logarithmic probability

I am trying to do sentiment analysis using Naive Bayes and have a doubt regarding log. While calculating posterior probability in Naive Bayes classifier, we apply log to prevent underflows and very ...
1k views

How does the beta prior - binomial conjugate theory hold in classifiers?

In our machine learning class, we were given an example of a naive bayes classifier. Say, you classify a day as being good/bad depending on 2 conditions (the "X" input) - weather(X1 - hot/cold) and ...
2k views

Small Probabilities in Naive Bayes

I am trying to implement Naive Bayes, but I am encountering a problem. I have 5000 word features. Hence, every sample is a binary vector of length 5000. The true labels are 1 or 0. The value of P(...
276 views

What non-Bayesian classifiers could be used in a naive Bayes model?

Bayes' theorem [is used] in the classifier's decision rule, but naive Bayes is not (necessarily) a Bayesian method. -Wikipedia. I have applied naive Bayes assumption to LDA, but it has a Bayes ...
141 views

Training and validating a naive gaussian bayes classifier

I've been reading up on the theory of naive bayes classifiers, specifically the ones in which the probability $p(x|c)$ is a random vector. The problem which I'm trying to solve takes a 4 dimensional ...
876 views

Classification problem: compare results of a decision tree, naive bayes and 1-nearest-neighbor classifier

These are the results of a classification problem using decision tree, naive bayes and 1-nearest-neighbor as classifiers. There are 10,000 data objects and these results were validated using 10-fold ...
10k views

Bernoulli NB vs MultiNomial NB, How to choose among different NB algorithms?

I want to understand the logic behind using a specific type of NB algorithm for a particular dataset. I read about Naive Bayes but still few things are unclear. According to my understanding of NB ...
478 views

Naive bayes performs worse than predicting the most common answer?

I have input X, with 22 binary features and 70000 examples. The target y is one of 4 possible categories. They are unbalanced, with the most common having a bit more than 51% of the data. When I train ...
3k views

Naive Bayes: Mix unigrams and bigrams for text classification?

I'm creating a naive bayes text classifier, but I'm wondering if it's a good idea to break the text up into both unigrams and bigrams. Should I only use one method? Will having both variations mess ...