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Test for differences in a cosinor model between components.

Source: R/test_cosinor.R
test_cosinor_components.Rd

Given a time variable and optional covariates, generate inference a cosinor fit. For the covariate named (or vector of covariates), this function performs a Wald test comparing the group with covariates equal to 1 to the group with covariates equal to 0. This may not be the desired result for continuous covariates.

Usage

test_cosinor_components(
  x,
  x_str = NULL,
  param = "amp",
  comparison_A = 1,
  comparison_B = 2,
  level_index = 0,
  ci_level = 0.95
)

Arguments

x

An cglmm object.

x_str

A character. The name of the grouping variable within which differences in the selected cosinor characteristic (amplitude or acrophase) will be tested. If there is no grouping variable in the model, then this can be left as NULL (default).

param

A character. Either "amp" or "acr" for testing differences in amplitude or acrophase, respectively.

comparison_A

An integer. Refers to the component number that is to act as the reference group. for the comparison.

comparison_B

An integer. Refers to the component number that is to act as the comparator group

level_index

An integer. If comparison_type = "components", level_index indicates which level of the grouping variable is being used for the comparison between components.

ci_level

The level for calculated confidence intervals. Defaults to 0.95.

Value

Returns a test_cosinor object.

Examples

data_2_component <- simulate_cosinor(
  n = 10000,
  mesor = 5,
  amp = c(2, 5),
  acro = c(0, pi),
  beta.mesor = 4,
  beta.amp = c(3, 4),
  beta.acro = c(0, pi / 2),
  family = "gaussian",
  n_components = 2,
  period = c(10, 12),
  beta.group = TRUE
)
mod_2_component <- cglmm(
  Y ~ group + amp_acro(times,
    n_components = 2, group = "group",
    period = c(10, 12)
  ),
  data = data_2_component
)
test_cosinor_components(mod_2_component, param = "amp", x_str = "group")
#> Test Details: 
#> Parameter being tested:
#> Amplitude
#> 
#> Comparison type:
#> components
#> 
#> Component indices used for comparison between groups: group
#> Reference component: 1
#> Comparator component: 2
#> 
#> 
#> Global test: 
#> Statistic: 
#> 8884.85
#> 
#> P-value: 
#> 0
#> 
#> 
#> Individual tests:
#> Statistic: 
#> 94.26
#> 
#> P-value: 
#> 0
#> 
#> Estimate and 95% confidence interval:
#> 2.95 (2.89 to 3.01)