The hardest part of sports analytics is getting data! Not for nothing there are companies, which earn their money just with sports data. But if you are not able or do not want to pay such amounts of money, you got just one possibility: scraping the data from the Web. In an older post, I described a R web scraper. As this one was no longer working, I needed a new one. What brings us to this post. This time I will describe, how to create a web scrapper for static HTML sites with Python and how you are able to implement such a web scrapper as a User Defined Function (UDF) in Exasol.
There is one big reason, why I have chosen Exasol as a database for my football analytics and predictions: Exasol is capable of executing Python and R code inside the database. Your are able to put your statistical calculations and predictive models to your data. The feature User Defined Functions (UDFs) provides the possibility to implement every logic which you normally code in Python or R. This is a really efficient way to extent plain SQL with some predictive functionality like the execution of TensorFlow models.
In this blog post I will explain, how you extend the Exasol community edition with all needed Python3 packages to execute Tensorflow models. Additionally with the latest update I also added the packages and description needed for all my web scrapping scripts.
As mentioned in the last post, I am now going to use TensorFlow to build my first own predictive model. But before, there are several small steps, which need to be taken. At first I want to explain, how your able to read and write data via a Python script into Exasol. This is needed to read the different predictive variables and write back results of a prediction into the database when developing models.
Everyone, who follows my blog, will have noticed, that I did not published any post for a long time. This was because I first could publish my first article for the DOAG Business News and after that had two presentations at the DOAG conference.
In the first part Prepare data: football-data.co.uk (part 1) I described how the Data Vault model for the data of football-data.co.uk looks like. In the second part I will now focus on loading data into the Data Vault model. With the overall analytical architecture in mind this equates the data integration process between the stage layer and the raw data layer.
In the post Gather data: football-data.co.uk I described, how you can load CSV data into the Exasol database. As the data is now available at the Stage Layer in the database, I must now prepare the data and persist it at the Raw Data Layer, so that I can easily use it for building predictive models.
With part 1 of this post I want to explain, what Data Vault modeling is and how the Data Vault model for the data structure of football-data.co.uk looks like. With part 2 I will explain, how you load data into the developed Data Vault model.
When I started this project, my biggest problem was to find a source for historic football statistics and historic football odds. Fortunately, I found Joseph Buchdahl’s website football-data.co.uk. This website is just great! He offers CSV files for 22 football leagues and about 19 seasons. He updates the data mostly two times a week. So I used this data as the starting point for my analytical system.
As described in How to beat the bookie: Value Betting I want to use Value Betting to beat the bookie. To identify value, I have to be able to calculate the probability of a specific sports event (e.g. Home-Win for Team A) as accurately as possible. Therefor, I have to develop, test, simulate and process different predictive models. As a DWH architect I know, that a good data architecture helps a lot to support such a developing process. That’s why I formed the concept of the TripleA DWH – the Advanced Agile Analytical Data Warehouse – a data architecture aimed to automate data science processes.