Dan Watkins

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Practical Machine Learning wk 4
Results from my project for practical machine learning, week 4, from the Johns Hopkins Data Science Specialization on Coursera.
Shiny Cluster Demo Presentation Pitch
A presentation pitching the functionality of my shiny app, found at
Leaflet Demo
Simple demo of leaflet plotting the top 100 world cities by population, with map interactivity and scaled population bubbles.
Statistical Inference, Project 2
Exploring the CLT via simulation and using 1- and 2-sample t-tests to make statistical inferences.
Machine Learning: Combining Predictors
An example of creating a generalized additive model using a linear model and a random forest model.
Machine Learning: Random Forests and Boosting
From week 3 of Coursera's "Practical Machine Learning" in the Data Science Specialization.
Machine Learning: Trees and Bagging
Notes from week 3 of the Coursera Data Science Specialization series.
Machine Learning: Regression Modeling
Example of creating single- and multi-variate regression.models to predict wage data.
Machine Learning: Preprocessing and PCA/SVD
More machine learning, now using principle component analysis to preprocess the data.
Practical Machine Learning, Week 2
Data slicing, K-folds cross validation, k-nearest neighbor imputation, variable transformations (standardization, BoxCox transform).
Basic Machine Learning Example
Using the caret package and the kernlab "spam" data set, I fit a basic GLM to predict whether an email is spam/notspam.
Data Cleaning Example
An assignment for a Data Cleaning class. The script downloads a machine-learning data set with a total of 10299 observations, unzips it, reads in the relevant data from 5 files, combines them into a single tidy data set ordered by participant and activity.
Reproducible Research, Project 1
Basic analysis on a simple activity tracking data set, available in code.
Reproducible Research, Project 2
This analysis is an exercise in literate programming using the knitr package in R. It uses the U.S. National Oceanic and Atmospheric Administration's (NOAA) storm database, with documentation available at: The analysis looks at 902297 observations of severe weather data with the intention of answering questions related to fatalities, injuries, and financial impact.