% Generated by roxygen2: do not edit by hand % Please edit documentation in R/rope.R \name{rope} \alias{rope} \alias{rope.numeric} \alias{rope.stanreg} \alias{rope.brmsfit} \title{Region of Practical Equivalence (ROPE)} \usage{ rope(x, ...) \method{rope}{numeric}(x, range = "default", ci = 0.9, verbose = TRUE, ...) \method{rope}{stanreg}(x, range = "default", ci = 0.9, effects = c("fixed", "random", "all"), parameters = NULL, verbose = TRUE, ...) \method{rope}{brmsfit}(x, range = "default", ci = 0.9, effects = c("fixed", "random", "all"), component = c("conditional", "zi", "zero_inflated", "all"), parameters = NULL, verbose = TRUE, ...) } \arguments{ \item{x}{Vector representing a posterior distribution. Can also be a \code{stanreg} or \code{brmsfit} model.} \item{...}{Currently not used.} \item{range}{ROPE's lower and higher bounds. Should be a vector of length two (e.g., \code{c(-0.1, 0.1)}) or \code{"default"}. If \code{"default"}, the range is set to \code{c(-0.1, 0.1)} if input is a vector, and \code{x +- 0.1*SD(response)} if a Bayesian model is provided.} \item{ci}{The Credible Interval (CI) probability, corresponding to the proportion of HDI, to use.} \item{verbose}{Toggle off warnings.} \item{effects}{Should results for fixed effects, random effects or both be returned? Only applies to mixed models. May be abbreviated.} \item{parameters}{Regular expression pattern that describes the parameters that should be returned. Meta-parameters (like \code{lp__} or \code{prior_}) are filtered by default, so only parameters that typically appear in the \code{summary()} are returned. Use \code{parameters} to select specific parameters for the output.} \item{component}{Should results for all parameters, parameters for the conditional model or the zero-inflated part of the model be returned? May be abbreviated. Only applies to \pkg{brms}-models.} } \description{ Compute the proportion (in percentage) of the HDI (default to the 90\% HDI) of a posterior distribution that lies within a region of practical equivalence. } \details{ Statistically, the probability of a posterior distribution of being different from 0 does not make much sense (the probability of it being different from a single point being infinite). Therefore, the idea underlining ROPE is to let the user define an area around the null value enclosing values that are \emph{equivalent to the null} value for practical purposes (\cite{Kruschke 2010, 2011, 2014}). \cr \cr Kruschke (2018) suggests that such null value could be set, by default, to the -0.1 to 0.1 range of a standardized parameter (negligible effect size according to Cohen, 1988). This could be generalized: For instance, for linear models, the ROPE could be set as \code{0 +/- .1 * sd(y)}. This ROPE range can be automatically computed for models using the \link{rope_range} function. \cr \cr Kruschke (2010, 2011, 2014) suggests using the proportion of the 95\% (or 90\%, considered more stable) \link[=hdi]{HDI} that falls within the ROPE as an index for "null-hypothesis" testing (as understood under the Bayesian framework, see \link[=equivalence_test]{equivalence_test}). } \examples{ library(bayestestR) rope(x = rnorm(1000, 0, 0.01), range = c(-0.1, 0.1)) rope(x = rnorm(1000, 0, 1), range = c(-0.1, 0.1)) rope(x = rnorm(1000, 1, 0.01), range = c(-0.1, 0.1)) rope(x = rnorm(1000, 1, 1), ci = c(.90, .95)) \dontrun{ library(rstanarm) model <- rstanarm::stan_glm(mpg ~ wt + cyl, data = mtcars) rope(model) rope(model, ci = c(.90, .95)) library(brms) model <- brms::brm(mpg ~ wt + cyl, data = mtcars) rope(model) rope(model, ci = c(.90, .95)) } } \references{ \itemize{ \item Cohen, J. (1988). Statistical power analysis for the behavioural sciences. \item Kruschke, J. K. (2010). What to believe: Bayesian methods for data analysis. Trends in cognitive sciences, 14(7), 293-300. \doi{10.1016/j.tics.2010.05.001}. \item Kruschke, J. K. (2011). Bayesian assessment of null values via parameter estimation and model comparison. Perspectives on Psychological Science, 6(3), 299-312. \doi{10.1177/1745691611406925}. \item Kruschke, J. K. (2014). Doing Bayesian data analysis: A tutorial with R, JAGS, and Stan. Academic Press. \doi{10.1177/2515245918771304}. \item Kruschke, J. K. (2018). Rejecting or accepting parameter values in Bayesian estimation. Advances in Methods and Practices in Psychological Science, 1(2), 270-280. \doi{10.1177/2515245918771304}. } }