As Google learned, predicting the spread of influenza, even with mountains of data, is notoriously difficult. Nonetheless, bioinformatician and R user Shirin Glander has created a two-part tutorial about predicting flu deaths with R (part 2 here). The analysis is based on just 136 cases of influenza A H7N9 in China in 2013 (data provided in the outbreaks package) so the intent was not to create a generally predictive model, but by providing all of the R code and graphics Shirin has created a useful example of real-word predictive modeling with R. The tutorial covers loading and cleaning the data (including a nice example of using the mice package to impute missing values) and begins with some exploratory data visualizations. I was particularly impressed by the use of density charts (using the stat_density2d ggplot2 aesthetic) to highlight differences in the scatterplots of flu cases ending in death and recovery. Decision trees (implemented using rpart and visualized using fancyRpartPlot from the rattle package) Random Forests (using caret's "rf" training method) Elastic-Net Regularized Generalized Linear Models (using caret's "glmnet" training method) K-nearest neighbors clustering (using caret's "kknn" training method) Penalized Discriminant Analysis (using caret's "pda" training method) and in Part 2, Extreme gradient boosting using the xgboost package and various preprocessing techniques from the caret package Due to the limited data size, there's not too much difference between the models: in each case, 13-15 of the 23 cases were classified correctly.

Calculus is not prerequisite to learn a lot of ML algorithms such as KNN, Naive Bayes, Decsion Trees, Random Forest, boosting etc and similar methods. However, if you wanna go the route for neural nets or deep learning, you need to figure out calculus because algorithms such as backpropagation uses them a lot. Also Gradient boosting and similar type of algorithms will require calculus knowledge.

This plugin currently works with the CLI version and python version. The maximum number of nodes needed for a given tree depth d is 2d 1 - 1. The maximum number of nodes on any given level is 2d. Data is stored in a sparse format. For example, missing values produced by one hot encoding are not stored.

They took the NYC Data Science Academy 12-week full-time data science bootcamp program from Sep. 23 to Dec. 18, 2015. The post was based on their fourth in-class project (due after the 8th week of the program). Walmart uses trip type classification to segment its shoppers and their store visits to better improve the shopping experience. Walmart's trip types are created from a combination of existing customer insights and purchase history data. The purpose of the Kaggle competition is to use only the purchase data provided to derive Walmart's classification labels.

Prerequisites: Working knowledge of Python is necessary if you want to run the source code that is provided. Basic knowledge of machine learning, especially ML classification techniques, would be helpful but it's not mandatory. Taught by a Stanford-educated, ex-Googler and an IIT, IIM - educated ex-Flipkart lead analyst. This team has decades of practical experience in quant trading, analytics and e-commerce. Completely Practical: This course has just enough theory to get you started with both Quant Trading and Machine Learning.

This post originally appeared on the Yhat blog. Yhat is a Brooklyn based company whose goal is to make data science applicable for developers, data scientists, and businesses alike. Yhat provides a software platform for deploying and managing predictive algorithms as REST APIs, while eliminating the painful engineering obstacles associated with production environments like testing, versioning, scaling and security. It can be used to on customer acquisition, retention, and churn or to in patients. Random forest is capable of regression and classification. It can handle a large number of features, and it's helpful for estimating which of your variables are important in the underlying data being modeled.

The Kaggle competitions are like formula racing for data science. Winners edge out competitors at the fourth decimal place and like Formula 1 race cars, not many of us would mistake them for daily drivers. The amount of time devoted and the sometimes extreme techniques wouldn't be appropriate in a data science production environment, but like paddle shifters and exotic suspensions, some of those improvement find their way into day-to-day life. Ensembles, or teams of predictive models working together, have been the core strategy for winning at Kaggle. They've been around for a long time but they are getting better.

A collection of minimal and clean implementations of machine learning algorithms. This project is targeting people who want to learn internals of ml algorithms or implement them from scratch. The code is much easier to follow than the optimized libraries and easier to play with. All algorithms are implemented in Python, using numpy, scipy and autograd.

Guest blog by Sebastian Raschka, originally posted here. If we tackle a supervised learning problem, my advice is to start with the simplest hypothesis space first. I.e., try a linear model such as logistic regression. If this doesn't work "well" (i.e., it doesn't meet our expectation or performance criterion that we defined earlier), I would move on to the next experiment. I would say that random forests are probably THE "worry-free" approach - if such a thing exists in ML: There are no real hyperparameters to tune (maybe except for the number of trees; typically, the more trees we have the better).

In a recent poll the question was raised "Will Data Scientists be replaced by software, and if so, when?" Are we really just grist for the AI mill? As part of the broader digital technology revolution we data scientists regard ourselves as part of the solution not part of the problem. But as part of this fast moving industry built on identifying and removing pain points it's possible to see that we are actually part of the problem. Seen as a good news / bad news story it goes like this. The good news is that advanced predictive analytics are gaining acceptance and penetration at an ever expanding rate.