| Type: | Package | 
| Title: | Cubic Spline Fitting with Knot Selection | 
| Version: | 1.2.2 | 
| Date: | 2018-05-16 | 
| Author: | Eric Golinko | 
| Depends: | leaps | 
| Maintainer: | Eric Golinko <egolinko@gmail.com> | 
| Description: | Cubic spline fitting along with knot selection, includes support for additional variables. | 
| License: | GPL-2 | GPL-3 [expanded from: GPL (≥ 2)] | 
| Packaged: | 2018-05-18 02:04:06 UTC; egolinko | 
| Repository: | CRAN | 
| Date/Publication: | 2018-05-18 03:42:57 UTC | 
| RoxygenNote: | 5.0.1 | 
| NeedsCompilation: | no | 
Kpart
Description
Cubic spline regression using the absolute maximum deviate to determine potential knots. This version also includes support for addidtional independednt variables to be included in the model.
Details
| Package: | Kpart | 
| Type: | Package | 
| Version: | 1.2.2 | 
| Date: | 2012-08-02 | 
| License: | Open Source | 
~~ This package is intended for use with non-linearly associated data. The function part firsts selects points for cubic spline knots using an algorithm to find the absolute maximum deviate from the partition mean, then fits a best fitting model by using the best subset method and maximum adjR2. The function returns the values selected as knots in the model. The function part(d, outcomeVariable, splineTerm, additionalVars = NULL, K) takes five arguments. K is a positive integer that indicates how many equally spaced partitions the user would like to search.~~
– Recent update includes support for additional variables, 2016-07-23. –
Author(s)
Eric Golinko
Maintainer: egolinko@gmail.com
References
Golinko, Eric David. A min/max algorithm for cubic splines over k-partitions. Florida Atlantic University, 2012.
Golinko, Eric, and Lianfen Qian. "A Min. Max Algorithm for Spline Based Modeling of Violent Crime Rates in USA." arXiv preprint arXiv:1804.06806 (2018).
Fits a linear model based on spline terms with additional support for other independent variables.
Description
The user will input a data frame, then designate the variable that is the outcome. Then the spline term is selected along with any other independent variables. Finally, a number K partitions is chosen for the algorithm to search for potential cubic spline knots based on the spline term and partition.
Usage
part(d, outcomeVariable, splineTerm, additionalVars = NULL, K)
Arguments
| d | A data frame data set with column names. | 
| outcomeVariable | The variable from 'd' that is the outcome. | 
| splineTerm | The spline term, inherited from 'd'. | 
| additionalVars | A vector of additional variables to be included in the model. | 
| K | The number of evenly spaced partitions to be searched. | 
Value
| fits | The fitted values of the linear model. | 
| xhat | The entire feature matrix. | 
| coefs | The significant coefficients of the model. | 
| adjr2 | The adjusted R^2 value. | 
Author(s)
Eric Golinko
Examples
## for simple spline model.
data(LakeHuron)
d <- data.frame(seq(1875, 1972, 1), LakeHuron)
names(d) <- c('date', 'lh')
fit <- part(d = d, outcomeVariable = 'lh', splineTerm = 'date', K = 20)
fit
plot(d$date, d$lh)
lines(d$date, fit$fits, col = 'red')
## multivariate
data(freeny)
freeny$time <- as.numeric(rownames(freeny))
fit <- part(d = freeny, outcomeVariable = 'y',
    splineTerm = 'time', additionalVars = c('market.potential', 'income.level'), K =2)
fit$coefs