Title: An Implementation of the Additive Polynomial Design Matrix
Version: 1.0.0
Description: An implementation of the additive polynomial (AP) design matrix. It constructs and appends an AP design matrix to a data frame for use with longitudinal data subject to seasonality.
Depends: R (≥ 3.2.3)
License: GPL-3
LazyData: true
Imports: Matrix (≥ 1.2)
RoxygenNote: 5.0.1
Suggests: testthat
NeedsCompilation: no
Packaged: 2016-11-14 16:49:49 UTC; tylerm
Author: Tyler Matta [aut, cre], Quinn Lathrop [ctb], Yeow Meng Thum [ctb]
Maintainer: Tyler Matta <tyler.matta@gmail.com>
Repository: CRAN
Date/Publication: 2016-11-15 07:16:42

apdesign: AP coding apdesign returns a data frame with additive polynomial coding

Description

apdesign: AP coding apdesign returns a data frame with additive polynomial coding

Usage

apdesign(data, id_var, time_var, center_time, cycle_var, center_cycle,
  max_degree = c(1, 1))

Arguments

data

A data frame.

id_var

A character that indicates the subject identifier in data.

time_var

A character that indicates the within-cycle time indicator in data.

center_time

A numeric specifying the within-cycle time to center on.

cycle_var

A character that indicates the cycle indicator in data.

center_cycle

A numeric specifying the cycle to center on.

max_degree

A vector of numerics specifying the highest degree for each polynomial.

Value

Output will be a data frame.

Examples

id <- c(rep(1,10), rep(2, 10))
y <- c(c(10, 15, 21, 20, 23, 25, 27, 25, 28, 29), 
     c(12, 16, 18, 20, 20, 22, 28, 27, 29, 31))
time <- c(c(0.2, 0.5, 0.7), c(0.3, 0.6, 0.75, 0.89), c(0.1, 0.3, 0.8), 
        c(0.3, 0.6, 0.7, 0.85), c(0.2, 0.7, 0.79), c(0.2, 0.5, 0.75))
cycle <- c(rep(1, 3), rep(2, 4), rep(3, 3), rep(1, 4), rep(2, 3), rep(3, 3))
df <- data.frame(id, y, time, cycle)
apdesign(data = df, id = "id", time_var = "time", cycle_var = "cycle", 
         center_cycle = 1, center_time = 0, max_degree = c(2,1))

apdesign_i: AP coding for a single subject

Description

apdesign_i: AP coding for a single subject

Usage

apdesign_i(data, cycle_var, center_cycle, time_var, center_time,
  max_degree = c(1, 1), matricies = FALSE)

Arguments

data

A data frame.

cycle_var

A character that indicates the cycle indicator in data.

center_cycle

A numeric specifying the cycle to center on.

time_var

A character that indicates the within-cycle time indicator in data.

center_time

A numeric specifying the within-cycle time to center on.

max_degree

A vector of numerics specifying the highest degree for each polynomial.

matricies

If TRUE, will print the AP, D1 and D2 matricies.

Value

Output will be a matrix.

Examples

y <- c(10, 15, 21, 20, 23, 25, 27, 25, 28, 29)
time <- c(c(0.2, 0.5, 0.7), c(0.3, 0.6, 0.75, 0.89), c(0.1, 0.3, 0.8))
cycle <- c(rep(1, 3), rep(2, 4), rep(3, 3))
df <- data.frame(y, time, cycle)
apdesign_i(data = df, time_var = "time", cycle_var = "cycle", 
         center_cycle = 1, center_time = 0, max_degree = c(2,1))

Repeated measures data over three years

Description

A dataset of longitudinal responses of 36 study participants over a three years span.

Usage

indv_change

Format

A data frame with 234 observations and 5 variables:

id

subject identifier

cycle

cycle number

cycle_time

time since the start of the cycle, in weeks

start_time

time since the start of the study, in weeks

response

outcome measure

Data for a single time trend over three years

Description

A dataset of mean responses of study participants over a three years span.

Usage

mean_change

Format

A data frame with 9 observations and 4 variables:

cycle

cycle number

cycle_time

time since the start of the cycle, in weeks

start_time

time since the start of the study, in weeks

response

outcome measure