The purpose of this blog post is to introduce a
probabilistic classifier that is often implemented through computer software
called “Naive Bayes” which is essentially used for pattern recognition within
some data set. I will draw the majority of my understanding in order to write
this post from the this video.

He begins the video by explaining the structure of the
dataset necessary for the application of the Naïve Bayes classifier. From the video, the set up for the data
should follow this form.

D = ((x

^{(1)}, y_{1}), … , (x^{(n)},y_{(n)})) D is an algebraic expression for the data set._{ }In an attempt to make that more clear, the variable x^{(1) }represents a coordinate pair ( x_{1}^{(1)},x_{d}^{(1)}) where the superscript shows what point that coordinate belongs to and the subscript indexes that coordinate. X^{(i) }is a point in the space of R^{d}. Y_{i }belongs to some finite set. In the video, he states that y represents a finite set that will be the integers from 1 to n.
He mentions in
the video that there are several assumptions made when taking on a Naïve Bayes
approach to classification. Those assumptions are listed as the following.

1)
We assume we have a family of some set of
distributions parametrized by theta and these distributions will have the
following properties. Each of these is a joint distribution on x and y. So
here x is going to be in Rd and Y is a
class.

2)
P

_{Θ}(x,y) = P_{Θ}(x|y) P_{Θ}(y) = P_{Θ}(x_{1}|y) … P_{Θ}(x_{d}|y) P_{Θ}(y)
He mentions in the video that this second assumption
is very key to the Naïve Bayes classification approach and that what this
essential means is that the first expression of assumption 2 (P

_{Θ}(x,y) = P_{Θ}(x|y) P_{Θ}(y)) will factor to equal the second expression. What I essential draw from this is that we assume that P_{Θ}(x|y) factors out to be the probability of the first coordinate x given y up to the last coordinate of x given y.
3)
Assume that the points are independently,
identically distributed based on parameter Θ. He mentions that in this context, the coordinates x

_{1}… x_{n}are independent given y if (X,Y) ~ P_{Θ}_{.}
He finally makes
things a bit clearer at 7:35 in the video. He mentions that the main assumption
is a conditional independence assumption.

At this point,
he explains the “goal” of Naïve Bayes. Essentially he says that when some new x
enters the data set, we want to “predict” its y. He mentions that the algorithm
initiates by attempting to estimate the parameter Θ for which it is believed the distribution of the (x,y)s
follow. Theta is estimated from the data and then we compute the prediction of
y that maximizes over all possible classes the probability of that class given
the new x. Because we assume that P

_{Θ}(x|y) P_{Θ}(y) factors out to be = P_{Θ}(x_{1}|y) … P_{Θ}(x_{d}|y) P_{Θ}(y), we will attempt to maximize the prediction y across all x’s, and that value should give the new prediction for the value of y given to the new x. For a better understanding, please watch the video.
I can see that you are are genuinely passionate about this! great information.

ReplyDeletethank you...!

Big data training

Good anlaytics of Big data

ReplyDeleteGood and best blog your blog very nice

ReplyDeleteBig Data for telecom

Thank you so much for sharing this worthwhile to spent time on. You are running a really awesome blog. Keep up this good work Big Data Course in Chennai

ReplyDeleteLearning new technology would give oneself a true confidence in the current emerging Information Technology domain. With the knowledge of big data the most magnificent cloud computing technology one can go the peek of data processing. As there is a drastic improvement in this field everyone are showing much interest in pursuing this technology. Your content tells the same about evolving technology. Thanks for sharing this.

ReplyDeleteHadoop Training in Chennai | Big Data Training | Big Data Course in Chennai | Best Hadoop Training in Chennai

Wonderful blog.. Thanks for sharing informative blog

ReplyDeleteTraining on CSTM/CSQP/CISQA

I have finally found a Worth able content to read. The way you have presented information here is quite impressive. I have bookmarked this page for future use. Thanks for sharing content like this once again. Keep sharing content like this.

ReplyDeleteSoftware testing training in chennai | Software testing course | Manual testing training in Chennai

There is a huge demand for professional big data analysts who are able to use the software which is used to process the big data in order to get accurate results. MNC's are looking for professionals who can process their data so that they can get into a accurate business decision which would eventually help them to earn more profits, they can serve their customers better, and their risk is lowered.

ReplyDeletebig data training in chennai|big data training|big data course in chennai|big data training chennai|big data hadoop training in chennai

Thanks for your informative article.

ReplyDeletemvc training in chennai

Your blog is really nice and informative. Thanks for sharing this post. Keep posting.

ReplyDeletedatastage training in chennai

• thanks for ur valuable information about informatica.

ReplyDeleteoracle training in chennai

• such a good website and given to more information thanks! and more visit.

ReplyDeleteoracle training inchennai

Thanks for sharing this valuable information.

ReplyDeletelenovo thinkpad service center chennai

lenovo laptop service center in chennai

lenovo ideapad service center chennai

web design training in chennai

ReplyDeletephp training in chennai

dot net training in chennai

java training in chennai

embedded training in chennai

very useful blogs.

ReplyDeletehotels near us consulate chennai

hotels near apollo hospital chennai

hotels near uk embassy chennai

hotels near german consulate chennai

hotels near sankara nethralaya chennai

business class hotels in chennai

Great and useful article. Creating content regularly is very tough. Your points are motivated me to move on

ReplyDeleteSEO Company in Chennai

Finding the time and actual effort to create a superb article like this is great thing. I’ll learn many new stuff right here! Good luck for the next post buddy..

ReplyDeleteFresher Jobs

Fresher Opening

Thanks for sharing Valuable information about Bigdata. This post is really helped me a lot. Keep sharing........... If it possible share some more tutorials???????????

ReplyDelete

ReplyDeleteThis is excellent information. It is amazing and wonderful to visit your site.Thanks for sharing this information,this is useful to me...

Android Training in Chennai

Ios Training in Chennai