Simple machine learning in R - Decision Trees

Now that the land registry data has been imported and had some initial exploratory work done to it lets have a go at making a price prediction model. I’ll use a small subset of the data and initially only try to predict whether or not the house is worth more or less than £500k, rather than the more complicated process of predicting the price. The code used in this post is largely based upon the DataCamp course “Introduction to Machine Learning”. Code for this project is on my GitHub page here. This post focuses on decision trees using the package rpart. Read More

Land Registry Data

My computer has been struggling with some of the code I’ve been trying to run, it is pretty old and doesn’t have enough memory for large datasets in R. So rather than buy a better laptop I’ve set up an Amazon Web Service account and using this guide set up a computer so I don’t have to use mine. I’m only using the free one for now but if I want to have a go at processing something larger this will allow me to pay a small fee to use a more powerful machine for a short period of time.

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Looping over a string in SAS

In SAS it is easy to loop a macro between two numbers

%DO I=1 %TO 10;
...
%END;

But if you have a list of non-sequential  numbers or text you want to run your macro over, e.g. a list of towns, it can be a bit trickier. This SUGI paper gives a macro which lets you do just that. A few years ago I looked at that macro and didn't really understand how it worked and not wanting to use code I didn't understand I wrote my own version.

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