[Lme4-commits] r1512 - branches/roxygen/R

noreply at r-forge.r-project.org noreply at r-forge.r-project.org
Tue Jan 24 23:07:10 CET 2012


Author: dmbates
Date: 2012-01-24 23:07:09 +0100 (Tue, 24 Jan 2012)
New Revision: 1512

Added:
   branches/roxygen/R/lme4Eigen-package.R
Log:
Place-holder for data set documentation.


Added: branches/roxygen/R/lme4Eigen-package.R
===================================================================
--- branches/roxygen/R/lme4Eigen-package.R	                        (rev 0)
+++ branches/roxygen/R/lme4Eigen-package.R	2012-01-24 22:07:09 UTC (rev 1512)
@@ -0,0 +1,478 @@
+### roxygen2 documentation for data sets in the package
+
+##' Breakage angle of chocolate cakes
+##' 
+##' Data on the breakage angle of chocolate cakes made with three different
+##' recipes and baked at six different temperatures.  This is a split-plot
+##' design with the recipes being whole-units and the different temperatures
+##' being applied to sub-units (within replicates). The experimental notes
+##' suggest that the replicate numbering represents temporal ordering.
+##' 
+##' The \code{replicate} factor is nested within the \code{recipe} factor, and
+##' \code{temperature} is nested within \code{replicate}.
+##' 
+##' @name cake
+##' @docType data
+##' @format A data frame with 270 observations on the following 5 variables.
+##'   \describe{
+##'     \item{\code{replicate}}{a factor with levels \code{1} to \code{15}}
+##'     \item{\code{recipe}}{a factor with levels \code{A}, \code{B} and \code{C}}
+##'     \item{\code{temperature}}{an ordered factor with levels \code{175}
+##'       < \code{185} < \code{195} < \code{205} < \code{215} < \code{225}}
+##'     \item{\code{angle}}{a numeric vector giving the angle at which the
+##'       cake broke.}
+##'     \item{\code{temp}}{numeric value of the baking temperature (degrees F).}
+##'   }
+##' @references Cook, F. E. (1938) \emph{Chocolate cake, I. Optimum baking
+##' temperature}. Master's Thesis, Iowa State College.
+##' 
+##' Cochran, W. G., and Cox, G. M. (1957) \emph{Experimental designs}, 2nd Ed.
+##' New York, John Wiley \& Sons.
+##' 
+##' Lee, Y., Nelder, J. A., and Pawitan, Y. (2006) \emph{Generalized linear
+##' models with random effects. Unified analysis via H-likelihood}. Boca Raton,
+##' Chapman and Hall/CRC.
+##' @source Original data were presented in Cook (1938), and reported in Cochran
+##' and Cox (1957, p. 300).  Also cited in Lee, Nelder and Pawitan (2006).
+##' @keywords datasets
+##' @examples
+##' str(cake)
+##' ## 'temp' is continuous, 'temperature' an ordered factor with 6 levels
+##' 
+##' fm1 <- lmer(angle ~ recipe * temperature + (1|recipe:replicate), cake, REML= FALSE)
+##' print(fm1, corr=FALSE)
+##' fm2 <- lmer(angle ~ recipe + temperature + (1|recipe:replicate), cake, REML= FALSE)
+##' print(fm2, corr=FALSE)
+##' fm3 <- lmer(angle ~ recipe + temp        + (1|recipe:replicate), cake, REML= FALSE)
+##' fm3
+##' 
+##' ## and now "choose" :
+##' anova(fm3, fm2, fm1)
+##' 
+NULL
+
+##' Contagious bovine pleuropneumonia
+##' 
+##' Contagious bovine pleuropneumonia (CBPP) is a major disease of cattle in
+##' Africa, caused by a mycoplasma.  This dataset describes the serological
+##' incidence of CBPP in zebu cattle during a follow-up survey implemented in 15
+##' commercial herds located in the Boji district of Ethiopia.  The goal of the
+##' survey was to study the within-herd spread of CBPP in newly infected herds.
+##' Blood samples were quarterly collected from all animals of these herds to
+##' determine their CBPP status.  These data were used to compute the
+##' serological incidence of CBPP (new cases occurring during a given time
+##' period).  Some data are missing (lost to follow-up).
+##' 
+##' Serological status was determined using a competitive enzyme-linked
+##' immuno-sorbent assay (cELISA).
+##' 
+##' @name cbpp
+##' @docType data
+##' @format A data frame with 56 observations on the following 4 variables.
+##'   \describe{
+##'     \item{\code{herd}}{A factor identifying the herd (1 to 15).}
+##'     \item{\code{incidence}}{The number of new serological cases for a
+##'       given herd and time period.}
+##'     \item{\code{size}}{A numeric vector describing herd size at the
+##'       beginning of a given time period.}
+##'     \item{\code{period}}{A factor with levels \code{1} to \code{4}.}
+##'   }
+##' @source Lesnoff, M., Laval, G., Bonnet, P., Abdicho, S., Workalemahu, A.,
+##' Kifle, D., Peyraud, A., Lancelot, R., Thiaucourt, F. (2004) Within-herd
+##' spread of contagious bovine pleuropneumonia in Ethiopian highlands.
+##' \emph{Preventive Veterinary Medicine} \bold{64}, 27--40.
+##' @keywords datasets
+##' @examples
+##' 
+##' ## response as a matrix
+##' (m1 <- glmer(cbind(incidence, size - incidence) ~ period + (1 | herd),
+##'              cbpp, binomial, nAGQ=9L))
+##' ## response as a vector of probabilities and usage of argument "weights"
+##' m1p <- glmer(incidence / size ~ period + (1 | herd), weights = size,
+##'              cbpp, binomial, nAGQ=9L)
+##' ## Confirm that these are equivalent:
+##' stopifnot(all.equal(fixef(m1), fixef(m1p), tol = 1e-11),
+##'           all.equal(ranef(m1), ranef(m1p), tol = 1e-11),
+##'           TRUE)
+##' 
+##' for(m in c(m1, m1p)) {
+##'     cat("-------\n\nCall: ",
+##'         paste(format(getCall(m)), collapse="\n"), "\n")
+##'     print(logLik(m)); cat("AIC:", AIC(m), "\n") ; cat("BIC:", BIC(m),"\n")
+##' }
+##' stopifnot(all.equal(logLik(m1), logLik(m1p), tol = 1e-11),
+##'           all.equal(AIC(m1),    AIC(m1p),    tol = 1e-11),
+##'           all.equal(BIC(m1),    BIC(m1p),    tol = 1e-11))
+##' 
+##' ## GLMM with individual-level variability (accounting for overdispersion)
+##' cbpp$obs <- 1:nrow(cbpp)
+##' (m2 <- glmer(cbind(incidence, size - incidence) ~ period +
+##'     (1 | herd) +  (1|obs),
+##'               family = binomial, data = cbpp))
+##' 
+##' 
+NULL
+
+##' Yield of dyestuff by batch
+##' 
+##' The \code{Dyestuff} data frame provides the yield of dyestuff (Naphthalene
+##' Black 12B) from 5 different preparations from each of 6 different batchs of
+##' an intermediate product (H-acid).  The \code{Dyestuff2} data were generated
+##' data in the same structure but with a large residual variance relative to
+##' the batch variance.
+##' 
+##' The \code{Dyestuff} data are described in Davies and Goldsmith (1972) as
+##' coming from \dQuote{an investigation to find out how much the variation from
+##' batch to batch in the quality of an intermediate product (H-acid)
+##' contributes to the variation in the yield of the dyestuff (Naphthalene Black
+##' 12B) made from it.  In the experiment six samples of the intermediate,
+##' representing different batches of works manufacture, were obtained, and five
+##' preparations of the dyestuff were made in the laboratory from each sample.
+##' The equivalent yield of each preparation as grams of standard colour was
+##' determined by dye-trial.}
+##' 
+##' The \code{Dyestuff2} data are described in Box and Tiao (1973) as
+##' illustrating \dQuote{ the case where between-batches mean square is less
+##' than the within-batches mean square.  These data had to be constructed for
+##' although examples of this sort undoubtably occur in practice, they seem to
+##' be rarely published.}
+##' 
+##' @name Dyestuff
+##' @aliases Dyestuff Dyestuff2
+##' @docType data
+##' @format Data frames, each with 30 observations on the following 2 variables.
+##'   \describe{
+##'     \item{\code{Batch}}{a factor indicating the batch of the
+##'       intermediate product from which the preparation was created.}
+##'     \item{\code{Yield}}{the yield of dyestuff from the preparation
+##'       (grams of standard color).}
+##'   }
+##' @source O.L. Davies and P.L. Goldsmith (eds), \emph{Statistical Methods in
+##' Research and Production, 4th ed.}, Oliver and Boyd, (1972), section 6.4
+##' 
+##' G.E.P. Box and G.C. Tiao, \emph{Bayesian Inference in Statistical Analysis},
+##' Addison-Wesley, (1973), section 5.1.2
+##' @keywords datasets
+##' @examples
+##' 
+##' \dontshow{ # useful for the lme4-authors --- development, debugging, etc:
+##'  commandArgs()[-1]
+##'  if(FALSE) ## R environment variables:
+##'  local({ ne <- names(e <- Sys.getenv())
+##'          list(R    = e[grep("^R", ne)],
+##'               "_R" = e[grep("^_R",ne)]) })
+##'  Sys.getenv("R_ENVIRON")
+##'  Sys.getenv("R_PROFILE")
+##'  cat("R_LIBS:\n"); (RL <- strsplit(Sys.getenv("R_LIBS"), ":")[[1]])
+##'  nRL <- normalizePath(RL)
+##'  cat("and extra .libPaths():\n")
+##'  .libPaths()[is.na(match(.libPaths(), nRL))]
+##' 
+##'  sessionInfo()
+##'  pkgI <- function(pkgname) {
+##'    pd <- packageDescription(pkgname)
+##'    cat(sprintf("%s -- built: %s\n%*s -- dir  : %s\n",
+##'                pkgname, pd$Built, nchar(pkgname), "",
+##'                dirname(dirname(attr(pd, "file")))))
+##'  }
+##'  pkgI("Matrix")
+##'  pkgI("Rcpp")
+##'  pkgI("minqa")
+##'  pkgI("MatrixModels")
+##'  pkgI("lme4Eigen")
+##' }
+##' str(Dyestuff)
+##' dotplot(reorder(Batch, Yield) ~ Yield, Dyestuff,
+##'         ylab = "Batch", jitter.y = TRUE, aspect = 0.3,
+##'         type = c("p", "a"))
+##' dotplot(reorder(Batch, Yield) ~ Yield, Dyestuff2,
+##'         ylab = "Batch", jitter.y = TRUE, aspect = 0.3,
+##'         type = c("p", "a"))
+##' (fm1 <- lmer(Yield ~ 1|Batch, Dyestuff))
+##' (fm2 <- lmer(Yield ~ 1|Batch, Dyestuff2))
+##' 
+NULL
+
+##' Sparse Gauss-Hermite quadrature grids
+##'
+##' \code{GQN} contains the non-redundant quadrature nodes and weights for
+##' integration of a scalar function of a \code{d}-dimensional argument with
+##' respect to the density function of the \code{d}-dimensional Gaussian
+##' density function.  These are stored in a list of lists.  The outer list
+##' is indexed by the dimension, \code{d}, in the range of 1 to 20.  The inner
+##' list is indexed by \code{k}, the order of the quadrature.
+##'
+##' @note These are only the non-redundant nodes.  To regenerate the whole
+##' array of nodes, all possible permutations of axes and all possible
+##' combinations of \eqn{\pm 1}{+/- 1} must be applied to the axes.
+##' The function \code{\link{GQdk}} reproduces the entire array of nodes.
+##' @seealso \code{\link{GQdk}}
+##' @name GQN
+##' @docType data
+##' @format A list of lists.
+##' @examples
+##' GQN[[3]][[5]]
+##'
+NULL
+
+##' University Lecture/Instructor Evaluations by Students at ETH
+##' 
+##' University lecture evaluations by students at ETH Zurich, anonymized for
+##' privacy protection.  This is an interesting \dQuote{medium} sized example of
+##' a \emph{partially} nested mixed effect model.
+##' 
+##' The main goal of the survey is to find \dQuote{the best liked prof},
+##' according to the lectures given.  Statistical analysis of such data has been
+##' the basis for a (student) jury selecting the final winners.
+##' 
+##' The present data set has been anonymized and slightly simplified on purpose.
+##' 
+##' @name InstEval
+##' @docType data
+##' @format A data frame with 73421 observations on the following 7 variables.
+##'   \describe{
+##'     \item{\code{s}}{a factor with levels \code{1:2972} denoting
+##'       individual students.}
+##'     \item{\code{d}}{a factor with 1128 levels from \code{1:2160}, denoting
+##'       individual professors or lecturers.}% ("d": \dQuote{Dozierende} in German)
+##'     \item{\code{studage}}{an ordered factor with levels \code{2} <
+##'       \code{4} < \code{6} < \code{8}, denoting student's \dQuote{age}
+##'       measured in the \emph{semester} number the student has been enrolled.}
+##'     \item{\code{lectage}}{an ordered factor with 6 levels, \code{1} <
+##'       \code{2} < ... < \code{6}, measuring how many semesters back the
+##'       lecture rated had taken place.}
+##'     \item{\code{service}}{a binary factor with levels \code{0} and
+##'       \code{1}; a lecture is a \dQuote{service}, if held for a
+##'       different department than the lecturer's main one.}
+##'     \item{\code{dept}}{a factor with 14 levels from \code{1:15}, using a
+##'       random code for the department of the lecture.}
+##' 
+##'     \item{\code{y}}{a numeric vector of \emph{ratings} of lectures by
+##'       the students, using the discrete scale \code{1:5}, with meanings
+##'       of \sQuote{poor} to \sQuote{very good}.}
+##'   }
+##'   Each observation is one student's rating for a specific lecture
+##'   (of one lecturer, during one semester in the past).
+##' @keywords datasets
+##' @examples
+##' 
+##' str(InstEval)
+##' 
+##' head(InstEval, 16)
+##' xtabs(~ service + dept, InstEval)
+##' 
+NULL
+
+##' Paste strength by batch and cask
+##' 
+##' Strength of a chemical paste product; its quality depending on the delivery
+##' batch, and the cask within the delivery.
+##' 
+##' The data are described in Davies and Goldsmith (1972) as coming from
+##' \dQuote{ deliveries of a chemical paste product contained in casks where, in
+##' addition to sampling and testing errors, there are variations in quality
+##' between deliveries \dots{} As a routine, three casks selected at random from
+##' each delivery were sampled and the samples were kept for reference. \dots{}
+##' Ten of the delivery batches were sampled at random and two analytical tests
+##' carried out on each of the 30 samples}.
+##' 
+##' @name Pastes
+##' @docType data
+##' @format A data frame with 60 observations on the following 4 variables.
+##'   \describe{
+##'     \item{\code{strength}}{paste strength.}
+##'     \item{\code{batch}}{delivery batch from which the sample was
+##'       sample.  A factor with 10 levels: \sQuote{A} to \sQuote{J}.}
+##'     \item{\code{cask}}{cask within the delivery batch from which the
+##'       sample was chosen.  A factor with 3 levels: \sQuote{a} to
+##'       \sQuote{c}.}
+##'     \item{\code{sample}}{the sample of paste whose strength was assayed,
+##'       two assays per sample. A factor with 30 levels: \sQuote{A:a} to
+##'       \sQuote{J:c}.}
+##'   }
+##' @source O.L. Davies and P.L. Goldsmith (eds), \emph{Statistical Methods in
+##' Research and Production, 4th ed.}, Oliver and Boyd, (1972), section 6.5
+##' @keywords datasets
+##' @examples
+##' str(Pastes)
+##' dotplot(cask ~ strength | reorder(batch, strength), Pastes,
+##'         strip = FALSE, strip.left = TRUE, layout = c(1, 10),
+##'         ylab = "Cask within batch",
+##'         xlab = "Paste strength", jitter.y = TRUE)
+##' ## Modifying the factors to enhance the plot
+##' Pastes <- within(Pastes, batch <- reorder(batch, strength))
+##' Pastes <- within(Pastes, sample <- reorder(reorder(sample, strength),
+##'           as.numeric(batch)))
+##' dotplot(sample ~ strength | batch, Pastes,
+##'         strip = FALSE, strip.left = TRUE, layout = c(1, 10),
+##'         scales = list(y = list(relation = "free")),
+##'         ylab = "Sample within batch",
+##'         xlab = "Paste strength", jitter.y = TRUE)
+##' ## Four equivalent models differing only in specification
+##' (fm1 <- lmer(strength ~ (1|batch) + (1|sample), Pastes))
+##' (fm2 <- lmer(strength ~ (1|batch/cask), Pastes))
+##' (fm3 <- lmer(strength ~ (1|batch) + (1|batch:cask), Pastes))
+##' (fm4 <- lmer(strength ~ (1|batch/sample), Pastes))
+##' ## fm4 results in redundant labels on the sample:batch interaction
+##' head(ranef(fm4)[[1]])
+##' ## compare to fm1
+##' head(ranef(fm1)[[1]])
+##' ## This model is different and NOT appropriate for these data
+##' (fm5 <- lmer(strength ~ (1|batch) + (1|cask), Pastes))
+##' 
+##' L <- getME(fm1, "L")
+##' image(L, sub = "Structure of random effects interaction in pastes model")
+##' 
+NULL
+
+##' Variation in penicillin testing
+##' 
+##' Six samples of penicillin were tested using the \emph{B. subtilis} plate
+##' method on each of 24 plates.  The response is the diameter (mm) of the zone
+##' of inhibition of growth of the organism.
+##' 
+##' The data are described in Davies and Goldsmith (1972) as coming from an
+##' investigation to \dQuote{assess the variability between samples of
+##' penicillin by the \emph{B. subtilis} method.  I this test method a
+##' bulk-innoculated nutrient agar medium is poured into a Petri dish of
+##' approximately 90 mm. diameter, known as a plate.  When the medium has set,
+##' six small hollow cylinders or pots (about 4 mm. in diameter) are cemented
+##' onto the surface at equally spaced intervals.  A few drops of the penicillin
+##' solutions to be compared are placed in the respective cylinders, and the
+##' whole plate is placed in an incubator for a given time.  Penicillin diffuses
+##' from the pots into the agar, and this produces a clear circular zone of
+##' inhibition of growth of the organisms, which can be readily measured.  The
+##' diameter of the zone is related in a known way to the concentration of
+##' penicillin in the solution.}
+##' 
+##' @name Penicillin
+##' @docType data
+##' @format A data frame with 144 observations on the following 3 variables.
+##'   \describe{
+##'     \item{\code{diameter}}{diameter (mm) of the zone of inhibition of
+##'       the growth of the organism.}
+##'     \item{\code{plate}}{assay plate.  A factor with levels \sQuote{a} to
+##'       \sQuote{x}.}
+##'     \item{\code{sample}}{penicillin sample.  A factor with levels
+##'       \sQuote{A} to \sQuote{F}.}
+##'   }
+##' @source O.L. Davies and P.L. Goldsmith (eds), \emph{Statistical Methods in
+##' Research and Production, 4th ed.}, Oliver and Boyd, (1972), section 6.6
+##' @keywords datasets
+##' @examples
+##' 
+##' str(Penicillin)
+##' dotplot(reorder(plate, diameter) ~ diameter, Penicillin, groups = sample,
+##'         ylab = "Plate", xlab = "Diameter of growth inhibition zone (mm)",
+##'         type = c("p", "a"), auto.key = list(columns = 3, lines = TRUE,
+##'         title = "Penicillin sample"))
+##' (fm1 <- lmer(diameter ~ (1|plate) + (1|sample), Penicillin))
+##' 
+##' L <- getME(fm1, "L")
+##' image(L, main = "L",
+##'       sub = "Penicillin: Structure of random effects interaction")
+##' 
+NULL
+
+##' Reaction times in a sleep deprivation study
+##' 
+##' The average reaction time per day for subjects in a sleep deprivation study.
+##' On day 0 the subjects had their normal amount of sleep.  Starting that night
+##' they were restricted to 3 hours of sleep per night.  The observations
+##' represent the average reaction time on a series of tests given each day to
+##' each subject.
+##' 
+##' These data are from the study described in Belenky et al. (2003), for the
+##' sleep-deprived group and for the first 10 days of the study, up to the
+##' recovery period.
+##' 
+##' @name sleepstudy
+##' @docType data
+##' @format A data frame with 180 observations on the following 3 variables.
+##'   \describe{
+##'     \item{\code{Reaction}}{Average reaction time (ms)}
+##'     \item{\code{Days}}{Number of days of sleep deprivation}
+##'     \item{\code{Subject}}{Subject number on which the observation was made.}
+##'   }
+##' @references Gregory Belenky, Nancy J. Wesensten, David R. Thorne, Maria L.
+##' Thomas, Helen C. Sing, Daniel P. Redmond, Michael B. Russo and Thomas J.
+##' Balkin (2003) Patterns of performance degradation and restoration during
+##' sleep restriction and subsequent recovery: a sleep dose-response study.
+##' \emph{Journal of Sleep Research} \bold{12}, 1--12.
+##' @keywords datasets
+##' @examples
+##' 
+##' str(sleepstudy)
+##' xyplot(Reaction ~ Days | Subject, sleepstudy, type = c("g","p","r"),
+##'        index = function(x,y) coef(lm(y ~ x))[1],
+##'        xlab = "Days of sleep deprivation",
+##'        ylab = "Average reaction time (ms)", aspect = "xy")
+##' (fm1 <- lmer(Reaction ~ Days + (Days|Subject), sleepstudy))
+##' (fm2 <- lmer(Reaction ~ Days + (1|Subject) + (0+Days|Subject), sleepstudy))
+##' 
+NULL
+
+
+##' Verbal Aggression item responses
+##' 
+##' These are the item responses to a questionaire on verbal aggression.  These
+##' data are used throughout De Boeck and Wilson, \emph{Explanatory Item
+##' Response Models} (Springer, 2004) to illustrate various forms of item
+##' response models.
+##' 
+##' 
+##' @name VerbAgg
+##' @docType data
+##' @format A data frame with 7584 observations on the following 13 variables.
+##'   \describe{
+##'     \item{\code{Anger}}{the subject's Trait Anger score as measured on
+##'       the State-Trait Anger Expression Inventory (STAXI)}
+##'     \item{\code{Gender}}{the subject's gender - a factor with levels
+##'       \code{M} and \code{F}}
+##'     \item{\code{item}}{the item on the questionaire, as a factor}
+##'     \item{\code{resp}}{the subject's response to the item - an ordered
+##'       factor with levels \code{no} < \code{perhaps} < \code{yes}}
+##'     \item{\code{id}}{the subject identifier, as a factor}
+##'     \item{\code{btype}}{behavior type - a factor with levels
+##'       \code{curse}, \code{scold} and \code{shout}}
+##'     \item{\code{situ}}{situation type - a factor with levels
+##'       \code{other} and \code{self} indicating other-to-blame and self-to-blame}
+##'     \item{\code{mode}}{behavior mode - a factor with levels \code{want}
+##'       and \code{do}}
+##'     \item{\code{r2}}{dichotomous version of the response - a factor with
+##'       levels \code{N} and \code{Y}}
+##'   }
+##' @references De Boeck and Wilson (2004), \emph{Explanatory Item Response
+##' Models}, Springer.
+##' @source \url{http://bear.soe.berkeley.edu/EIRM/}
+##' @keywords datasets
+##' @examples
+##' 
+##' str(VerbAgg)
+##' ## Show how  r2 := h(resp) is defined:
+##' with(VerbAgg, stopifnot( identical(r2, {
+##'      r <- factor(resp, ordered=FALSE); levels(r) <- c("N","Y","Y"); r})))
+##' 
+##' xtabs(~ item + resp, VerbAgg)
+##' xtabs(~ btype + resp, VerbAgg)
+##' round(100 * ftable(prop.table(xtabs(~ situ + mode + resp, VerbAgg), 1:2), 1))
+##' person <- unique(subset(VerbAgg, select = c(id, Gender, Anger)))
+##' if (require(lattice)) {   # is this necessary when the package depends on lattice?
+##'     densityplot(~ Anger, person, groups = Gender, auto.key = list(columns = 2),
+##'                 xlab = "Trait Anger score (STAXI)")
+##' }
+##' 
+##' \dontrun{## takes about 15 sec
+##' print(fmVA <- glmer(r2 ~ (Anger + Gender + btype + situ)^2 +
+##'                    (1|id) + (1|item), family = binomial, data =
+##'                    VerbAgg), corr=FALSE)
+##' }
+##'                        ## much faster but less accurate
+##' print(fmVA0 <- glmer(r2 ~ (Anger + Gender + btype + situ)^2 +
+##'                     (1|id) + (1|item), family = binomial, data =
+##'                     VerbAgg, nAGQ=0L), corr=FALSE)
+##' 
+NULL
+
+
+



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