# npregfast:
Nonparametric Estimation of Regression Models with Factor-by-Curve
Interactions

`npregfast`

is an R package for obtain nonparametric
estimates of regression models with or without factor-by-curve
interactions using local polynomial kernel smoothers or splines.
Additionally, a parametric model (allometric model) can be estimated.
Particular features of the package are facilities for fast smoothness
estimation, and the calculation of their first and second derivative.
Users can define the smoothers parameters. Confidence intervals
calculation is provided by bootstrap methods. Binning techniques were
applied to speed up computation in the estimation and testing
processes.

You can view a live interactive demo to see part of its capabilities
at http://sestelo.shinyapps.io/npregfast.

## Installation

`npregfast`

is available through both CRAN and GitHub.

Get the released version from CRAN:

`install.packages("npregfast")`

Or the development version from GitHub:

```
# install.packages("devtools")
devtools::install_github("sestelo/npregfast")
```