Sigmoid for Classifiers Decoded

decisionBoundary

Hello World,

Sigmoid really isn’t that complicated (once your understand it of course).  Some back knowledge in case you are coming at this totally fresh is that the Sigmoid function is used in machine learning primarily as a hypothesis function for classifiers.  What is interesting is that this same function is used for binary classifiers, multi-class classifiers and is the backbone of modern neural networks.

Here is the sigmoid function:    \frac{ 1 }{ 1 + e^{-z}}

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Machine Learning Study Group Recap – Week 1

Hello World!

So many of you who are here are probably part of the study group.  For those who are not or are perhaps referencing this at a later time, this is in regards to the following course on Coursera. If you would like to join our study group, please see one of the following meetup pages: Fort Lauderdale Machine Learning or Florida Dot Net.

Here in South Florida we have a strong Machine Learning and Data Science community and therefor it is easy to get a study group together.  This article is a recap from the first meeting of our study group.  Note that this first meeting is the week before the class started.  Therefor this article is a great introduction to machine learning, languages, commitments and more generally applicable questions and concerns.

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Linear Regression from Scratch

Hello World,

So today we will do a quick conversion from mathematical notations of Algebra into a real algorithm that can be executed.  Note we will not be covering gradient descent, but rather only cost functions, errors and execution of these to provide the framework for gradient descent.  Gradient descent has so many flavors that it deserves its own article.

So to the mathematical representation.

LinearRegression

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Miami’s top 10 Jail Bookings

Hello World!

So I’ve been working on building some interesting visualizations with open data.  Today I get to show off a really interesting one, not only will we discuss the visualization in depth, but also dive into how I built it.  And here it is, the top 10 bookings in Miami where the legend is in descending order for most common bookings holistically.

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Using Census Data to Help Pick your Child’s Name

Hello World!

So I had a life changing event this past Sunday at 8:55am 5/24/2015.  My first child was born!  Both child and wife are healthy and happy.  Everything is good in life.  Like many couples though, my wife and I struggled to find the right name for our child.  We didn’t want something too common, or was an old person name, or so rare and funky that nobody could spell it.  We also realized we just had a general lack in knowing what names were out there.  So after much debate and discussion over what to name her, I started doing a bit of an analysis using some census data.  I want to thank Jamie Dixon for providing the data that he found for use in his Dinner Nerds article.  The data itself can be found here.  This article will discuss the code used to go through all of the data and provide insights into child names.

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