README.Rmd

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# regista <img src="man/figures/logo.png" align="right" />

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## Overview

regista is a package for performing some of the common modelling tasks in soccer
analytics.

## Installation

regista is not currently available on CRAN but can be downloaded from github like so:

```{r, eval = FALSE}
# install.packages("devtools")
devtools::install_github("torvaney/regista")
```

## Examples

### Dixon-Coles

The ["Dixon-Coles model"](http://web.math.ku.dk/~rolf/teaching/thesis/DixonColes.pdf) is a modified poisson model, specifically designed for estimating teams' strengths and for predicting football matches. 

Regista provides an implementation of this model:

```{r, message = FALSE, warning = FALSE}
library(regista)

fit <- dixoncoles(hgoal, agoal, home, away, data = premier_league_2010)

print(fit)
```

A more flexible api is provided with `dixoncoles_ext`, which allows the base Dixon-Coles model to be extended arbitrarily.

`vignette("using-dixon-coles")` gives some simple examples for using the model. 
Additionally, there are more extensive examples and analyses using regista 
available at the following links:

 * [Modelling the World Cup with regista](http://www.statsandsnakeoil.com/2018/06/05/modelling-the-world-cup-with-regista/)
 * [Dixon Coles and xG: together at last](http://www.statsandsnakeoil.com/2018/06/22/dixon-coles-and-xg-together-at-last/)
 * [What a diff'rence xG makes](http://www.statsandsnakeoil.com/2018/07/15/what-a-diff-rence-xg-makes/)


Other options
---

* The [mezzala](https://github.com/Torvaney/mezzala) package provides similar functionality for Python.
* The [goalmodel](https://github.com/opisthokonta/goalmodel) R package contains an
implementation of the Dixon-Coles model, along with some additional method for
modelling the number of goals scored in sports games.