## Recently Published ##### Using Machine Learning to Detect Breast Cancer
In this R tutorial, we will go over the k-NN algorithm, a supervised classification machine learning model to detect the presence of breast cancer. ##### Detecting Junk Mail Using Naive Bayes Classification
Learn to implement the Naive Bayes Classification algorithm to classify email as junk or not junk. ##### Assess the Impact of Your Marketing Efforts Using Linear Regression
Learn how to use simple linear regression to analyze the impact of your advertising and marketing efforts on sales. ##### Using Regression Trees to Predict Baseball Salaries
A tutorial on constructing regression trees in R with an example using baseball players data to predict salary. ##### Linear Regression Using Dummy Variables
A very brief tutorial on how to create a regression model using dummy variables (i.e. variables that are qualitative). ##### SQL Fundamentals (Work in Progress)
Per many of my friends' requests, I've decided to publish a very basic tutorial on the fundamentals of SQL. It's still a work in progress, but I will continue to update it as much as possible. Side note: It's a bit ironic that I'm doing this since some dweeb decided to fire me for my inadequate SQL skills, despite him not being the one administering the whiteboard SQL exam (of which I passed). That dude was a dweeb. ##### GRE Quantitative Reasoning: Formulae, Rules & Properties, Shortcuts, and Misc. Strategies
A collection of mathematical formulae, rules and properties, shortcuts, and miscellaneous properties for the GRE Quantitative Reasoning section. ##### Time Series Regression with Stationary Variables: An Introduction to the ARDL Model
A brief overview on autoregressive, distributed-lag, and autoregressive distributed-lag (ARDL) models and how to implement these models using R's Dynamic Linear Models (dynlm) package. ##### Simultaneous Equation Models: Estimating Supply and Demand
An overview of simultaneous equation models, a statistical method for solving for a set of simultaneous linear equations. Estimating a set of simultaneous supply and demand functions isn't as simple as using least squares regression to estimate each function individually. In this example, I show the proper way to estimate a set of simultaneous supply and demand functions using a technique called two-staged least squares estimation. ##### Proving Social Media’s Business Worth: Stop Measuring ROI
The goal of measuring "social media ROI' is to prove social media's worth to an organization's overall business objectives. I propose a model that doesn't measure ROI, but instead directly captures the effect every dollar increase in social media investment has on a business's sales. ##### An Empirical Analysis of Okun's Law
Okun's Law is an economic concept that describes the relationship between the change in the US unemployment rate and the change in output, or real GDP. We examine the logic behind Okun's Law and conduct an empirical analysis to determine whether or not it still holds.  