diff --git a/R/bart.R b/R/bart.R
index e70cbdda..1c814dd3 100644
--- a/R/bart.R
+++ b/R/bart.R
@@ -1230,7 +1230,7 @@ saveBARTModelToJson <- function(object){
 #' @param object Object of type `bartmodel` containing draws of a BART model and associated sampling outputs.
 #' @param filename String of filepath, must end in ".json"
 #'
-#' @return NULL
+#' @return None
 #' @export
 #'
 #' @examples
diff --git a/R/data.R b/R/data.R
index d90265ae..4f35efc0 100644
--- a/R/data.R
+++ b/R/data.R
@@ -111,7 +111,7 @@ Outcome <- R6::R6Class(
         #' @description
         #' Update the current state of the outcome (i.e. partial residual) data by adding the values of `update_vector`
         #' @param update_vector Vector to be added to outcome
-        #' @return NULL
+        #' @return None
         add_vector = function(update_vector) {
             if (!is.numeric(update_vector)) {
                 stop("update_vector must be a numeric vector or 2d matrix")
@@ -128,7 +128,7 @@ Outcome <- R6::R6Class(
         #' @description
         #' Update the current state of the outcome (i.e. partial residual) data by subtracting the values of `update_vector`
         #' @param update_vector Vector to be subtracted from outcome
-        #' @return NULL
+        #' @return None
         subtract_vector = function(update_vector) {
             if (!is.numeric(update_vector)) {
                 stop("update_vector must be a numeric vector or 2d matrix")
@@ -145,7 +145,7 @@ Outcome <- R6::R6Class(
         #' @description
         #' Update the current state of the outcome (i.e. partial residual) data by replacing each element with the elements of `new_vector`
         #' @param new_vector Vector from which to overwrite the current data
-        #' @return NULL
+        #' @return None
         update_data = function(new_vector) {
             if (!is.numeric(new_vector)) {
                 stop("update_vector must be a numeric vector or 2d matrix")
diff --git a/R/forest.R b/R/forest.R
index 4a0680cb..224e8c7c 100644
--- a/R/forest.R
+++ b/R/forest.R
@@ -35,7 +35,7 @@ ForestSamples <- R6::R6Class(
         #' Append to a `ForestContainer` object from a json object
         #' @param json_object Object of class `CppJson`
         #' @param json_forest_label Label referring to a particular forest (i.e. "forest_0") in the overall json hierarchy
-        #' @return NULL
+        #' @return None
         append_from_json = function(json_object, json_forest_label) {
             forest_container_append_from_json_cpp(self$forest_container_ptr, json_object$json_ptr, json_forest_label)
         }, 
@@ -53,7 +53,7 @@ ForestSamples <- R6::R6Class(
         #' Append to a `ForestContainer` object from a json object
         #' @param json_string JSON string which parses into object of class `CppJson`
         #' @param json_forest_label Label referring to a particular forest (i.e. "forest_0") in the overall json hierarchy
-        #' @return NULL
+        #' @return None
         append_from_json_string = function(json_string, json_forest_label) {
             forest_container_append_from_json_string_cpp(self$forest_container_ptr, json_string, json_forest_label)
         }, 
@@ -799,6 +799,7 @@ createForest <- function(num_trees, leaf_dimension=1, is_leaf_constant=F, is_exp
 #' @param active_forest Current active forest
 #' @param forest_samples (Optional) Container of forest samples from which to re-initialize active forest. If not provided, active forest will be reset to an ensemble of single-node (i.e. root) trees.
 #' @param forest_num (Optional) Index of forest samples from which to initialize active forest. If not provided, active forest will be reset to an ensemble of single-node (i.e. root) trees.
+#' @return None
 #' @export
 #' 
 #' @examples
@@ -832,6 +833,7 @@ resetActiveForest <- function(active_forest, forest_samples=NULL, forest_num=NUL
 #' @param dataset Training dataset object
 #' @param residual Residual which will also be updated
 #' @param is_mean_model Whether the model being updated is a conditional mean model
+#' @return None
 #' @export
 #' 
 #' @examples
diff --git a/R/model.R b/R/model.R
index 534cf7bc..5dc1de69 100644
--- a/R/model.R
+++ b/R/model.R
@@ -125,7 +125,7 @@ ForestModel <- R6::R6Class(
         #' Update the current state of the outcome (i.e. partial residual) data by subtracting the current predictions of each tree. 
         #' This function is run after the `Outcome` class's `update_data` method, which overwrites the partial residual with an entirely new stream of outcome data.
         #' @param residual Outcome used to sample the forest
-        #' @return NULL
+        #' @return None
         propagate_residual_update = function(residual) {
             propagate_trees_column_vector_cpp(self$tracker_ptr, residual$data_ptr)
         }, 
@@ -133,7 +133,7 @@ ForestModel <- R6::R6Class(
         #' @description
         #' Update alpha in the tree prior
         #' @param alpha New value of alpha to be used
-        #' @return NULL
+        #' @return None
         update_alpha = function(alpha) {
             update_alpha_tree_prior_cpp(self$tree_prior_ptr, alpha)
         }, 
@@ -141,7 +141,7 @@ ForestModel <- R6::R6Class(
         #' @description
         #' Update beta in the tree prior
         #' @param beta New value of beta to be used
-        #' @return NULL
+        #' @return None
         update_beta = function(beta) {
             update_beta_tree_prior_cpp(self$tree_prior_ptr, beta)
         }, 
@@ -149,7 +149,7 @@ ForestModel <- R6::R6Class(
         #' @description
         #' Update min_samples_leaf in the tree prior
         #' @param min_samples_leaf New value of min_samples_leaf to be used
-        #' @return NULL
+        #' @return None
         update_min_samples_leaf = function(min_samples_leaf) {
             update_min_samples_leaf_tree_prior_cpp(self$tree_prior_ptr, min_samples_leaf)
         }, 
@@ -157,7 +157,7 @@ ForestModel <- R6::R6Class(
         #' @description
         #' Update max_depth in the tree prior
         #' @param max_depth New value of max_depth to be used
-        #' @return NULL
+        #' @return None
         update_max_depth = function(max_depth) {
             update_max_depth_tree_prior_cpp(self$tree_prior_ptr, max_depth)
         }
diff --git a/R/random_effects.R b/R/random_effects.R
index 38c47166..f9d0b70c 100644
--- a/R/random_effects.R
+++ b/R/random_effects.R
@@ -32,7 +32,7 @@ RandomEffectSamples <- R6::R6Class(
         #' @param num_components Number of "components" or bases defining the random effects regression
         #' @param num_groups Number of random effects groups
         #' @param random_effects_tracker Object of type `RandomEffectsTracker`
-        #' @return NULL
+        #' @return None
         load_in_session = function(num_components, num_groups, random_effects_tracker) {
             # Initialize
             self$rfx_container_ptr <- rfx_container_cpp(num_components, num_groups)
@@ -59,7 +59,7 @@ RandomEffectSamples <- R6::R6Class(
         #' @param json_rfx_container_label Label referring to a particular rfx sample container (i.e. "random_effect_container_0") in the overall json hierarchy
         #' @param json_rfx_mapper_label Label referring to a particular rfx label mapper (i.e. "random_effect_label_mapper_0") in the overall json hierarchy
         #' @param json_rfx_groupids_label Label referring to a particular set of rfx group IDs (i.e. "random_effect_groupids_0") in the overall json hierarchy
-        #' @return NULL (updates object in-place)
+        #' @return None
         append_from_json = function(json_object, json_rfx_container_label, json_rfx_mapper_label, json_rfx_groupids_label) {
             rfx_container_append_from_json_cpp(self$rfx_container_ptr, json_object$json_ptr, json_rfx_container_label)
         }, 
@@ -83,7 +83,7 @@ RandomEffectSamples <- R6::R6Class(
         #' @param json_rfx_container_label Label referring to a particular rfx sample container (i.e. "random_effect_container_0") in the overall json hierarchy
         #' @param json_rfx_mapper_label Label referring to a particular rfx label mapper (i.e. "random_effect_label_mapper_0") in the overall json hierarchy
         #' @param json_rfx_groupids_label Label referring to a particular set of rfx group IDs (i.e. "random_effect_groupids_0") in the overall json hierarchy
-        #' @return NULL (updates object in-place)
+        #' @return None
         append_from_json_string = function(json_string, json_rfx_container_label, json_rfx_mapper_label, json_rfx_groupids_label) {
             # Append RFX objects
             rfx_container_append_from_json_string_cpp(self$rfx_container_ptr, json_string, json_rfx_container_label)
@@ -398,6 +398,7 @@ createRandomEffectsModel <- function(num_components, num_groups) {
 #' @param rfx_samples Object of type `RandomEffectSamples`.
 #' @param sample_num Index of sample stored in `rfx_samples` from which to reset the state of a random effects model. Zero-indexed, so resetting based on the first sample would require setting `sample_num = 0`.
 #' @param sigma_alpha_init Initial value of the "working parameter" scale parameter.
+#' @return None
 #' @export
 #' 
 #' @examples
@@ -439,6 +440,7 @@ resetRandomEffectsModel <- function(rfx_model, rfx_samples, sample_num, sigma_al
 #' @param rfx_dataset Object of type `RandomEffectsDataset`.
 #' @param residual Object of type `Outcome`.
 #' @param rfx_samples Object of type `RandomEffectSamples`.
+#' @return None
 #' @export
 #' 
 #' @examples
@@ -476,6 +478,7 @@ resetRandomEffectsTracker <- function(rfx_tracker, rfx_model, rfx_dataset, resid
 #' @param sigma_xi_init Initial value of the "group parameters" scale parameter.
 #' @param sigma_xi_shape Shape parameter for the inverse gamma variance model on the group parameters.
 #' @param sigma_xi_scale Scale parameter for the inverse gamma variance model on the group parameters.
+#' @return None
 #' @export
 #' 
 #' @examples
@@ -522,6 +525,7 @@ rootResetRandomEffectsModel <- function(rfx_model, alpha_init, xi_init, sigma_al
 #' @param rfx_model Object of type `RandomEffectsModel`.
 #' @param rfx_dataset Object of type `RandomEffectsDataset`.
 #' @param residual Object of type `Outcome`.
+#' @return None
 #' @export
 #' 
 #' @examples
diff --git a/R/serialization.R b/R/serialization.R
index 14463c52..d5d4e046 100644
--- a/R/serialization.R
+++ b/R/serialization.R
@@ -45,7 +45,7 @@ CppJson <- R6::R6Class(
         #' @description
         #' Convert a forest container to json and add to the current `CppJson` object
         #' @param forest_samples `ForestSamples` R class
-        #' @return NULL
+        #' @return None
         add_forest = function(forest_samples) {
             forest_label <- json_add_forest_cpp(self$json_ptr, forest_samples$forest_container_ptr)
             self$num_forests <- self$num_forests + 1
@@ -55,7 +55,7 @@ CppJson <- R6::R6Class(
         #' @description
         #' Convert a random effects container to json and add to the current `CppJson` object
         #' @param rfx_samples `RandomEffectSamples` R class
-        #' @return NULL
+        #' @return None
         add_random_effects = function(rfx_samples) {
             rfx_container_label <- json_add_rfx_container_cpp(self$json_ptr, rfx_samples$rfx_container_ptr)
             self$rfx_container_labels <- c(self$rfx_container_labels, rfx_container_label)
@@ -72,7 +72,7 @@ CppJson <- R6::R6Class(
         #' @param field_name The name of the field to be added to json
         #' @param field_value Numeric value of the field to be added to json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which to place the value
-        #' @return NULL
+        #' @return None
         add_scalar = function(field_name, field_value, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 json_add_double_cpp(self$json_ptr, field_name, field_value)
@@ -86,7 +86,7 @@ CppJson <- R6::R6Class(
         #' @param field_name The name of the field to be added to json
         #' @param field_value Integer value of the field to be added to json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which to place the value
-        #' @return NULL
+        #' @return None
         add_integer = function(field_name, field_value, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 json_add_integer_cpp(self$json_ptr, field_name, field_value)
@@ -100,7 +100,7 @@ CppJson <- R6::R6Class(
         #' @param field_name The name of the field to be added to json
         #' @param field_value Numeric value of the field to be added to json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which to place the value
-        #' @return NULL
+        #' @return None
         add_boolean = function(field_name, field_value, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 json_add_bool_cpp(self$json_ptr, field_name, field_value)
@@ -114,7 +114,7 @@ CppJson <- R6::R6Class(
         #' @param field_name The name of the field to be added to json
         #' @param field_value Numeric value of the field to be added to json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which to place the value
-        #' @return NULL
+        #' @return None
         add_string = function(field_name, field_value, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 json_add_string_cpp(self$json_ptr, field_name, field_value)
@@ -128,7 +128,7 @@ CppJson <- R6::R6Class(
         #' @param field_name The name of the field to be added to json
         #' @param field_vector Vector to be stored in json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which to place the value
-        #' @return NULL
+        #' @return None
         add_vector = function(field_name, field_vector, subfolder_name = NULL) {
             field_vector <- as.numeric(field_vector)
             if (is.null(subfolder_name)) {
@@ -143,7 +143,7 @@ CppJson <- R6::R6Class(
         #' @param field_name The name of the field to be added to json
         #' @param field_vector Vector to be stored in json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which to place the value
-        #' @return NULL
+        #' @return None
         add_integer_vector = function(field_name, field_vector, subfolder_name = NULL) {
             field_vector <- as.numeric(field_vector)
             if (is.null(subfolder_name)) {
@@ -158,7 +158,7 @@ CppJson <- R6::R6Class(
         #' @param field_name The name of the field to be added to json
         #' @param field_vector Character vector to be stored in json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which to place the value
-        #' @return NULL
+        #' @return None
         add_string_vector = function(field_name, field_vector, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 json_add_string_vector_cpp(self$json_ptr, field_name, field_vector)
@@ -171,7 +171,7 @@ CppJson <- R6::R6Class(
         #' Add a list of vectors (as an object map of arrays) to the json object under the name "field_name"
         #' @param field_name The name of the field to be added to json
         #' @param field_list List to be stored in json
-        #' @return NULL
+        #' @return None
         add_list = function(field_name, field_list) {
             stopifnot(sum(!sapply(field_list, is.vector))==0)
             list_names <- names(field_list)
@@ -186,7 +186,7 @@ CppJson <- R6::R6Class(
         #' Add a list of vectors (as an object map of arrays) to the json object under the name "field_name"
         #' @param field_name The name of the field to be added to json
         #' @param field_list List to be stored in json
-        #' @return NULL
+        #' @return None
         add_string_list = function(field_name, field_list) {
             stopifnot(sum(!sapply(field_list, is.vector))==0)
             list_names <- names(field_list)
@@ -201,7 +201,7 @@ CppJson <- R6::R6Class(
         #' Retrieve a scalar value from the json object under the name "field_name" (with optional subfolder "subfolder_name")
         #' @param field_name The name of the field to be accessed from json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which the field is stored
-        #' @return NULL
+        #' @return None
         get_scalar = function(field_name, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 stopifnot(json_contains_field_cpp(self$json_ptr, field_name))
@@ -217,7 +217,7 @@ CppJson <- R6::R6Class(
         #' Retrieve a integer value from the json object under the name "field_name" (with optional subfolder "subfolder_name")
         #' @param field_name The name of the field to be accessed from json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which the field is stored
-        #' @return NULL
+        #' @return None
         get_integer = function(field_name, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 stopifnot(json_contains_field_cpp(self$json_ptr, field_name))
@@ -233,7 +233,7 @@ CppJson <- R6::R6Class(
         #' Retrieve a boolean value from the json object under the name "field_name" (with optional subfolder "subfolder_name")
         #' @param field_name The name of the field to be accessed from json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which the field is stored
-        #' @return NULL
+        #' @return None
         get_boolean = function(field_name, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 stopifnot(json_contains_field_cpp(self$json_ptr, field_name))
@@ -249,7 +249,7 @@ CppJson <- R6::R6Class(
         #' Retrieve a string value from the json object under the name "field_name" (with optional subfolder "subfolder_name")
         #' @param field_name The name of the field to be accessed from json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which the field is stored
-        #' @return NULL
+        #' @return None
         get_string = function(field_name, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 stopifnot(json_contains_field_cpp(self$json_ptr, field_name))
@@ -265,7 +265,7 @@ CppJson <- R6::R6Class(
         #' Retrieve a vector from the json object under the name "field_name" (with optional subfolder "subfolder_name")
         #' @param field_name The name of the field to be accessed from json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which the field is stored
-        #' @return NULL
+        #' @return None
         get_vector = function(field_name, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 stopifnot(json_contains_field_cpp(self$json_ptr, field_name))
@@ -281,7 +281,7 @@ CppJson <- R6::R6Class(
         #' Retrieve an integer vector from the json object under the name "field_name" (with optional subfolder "subfolder_name")
         #' @param field_name The name of the field to be accessed from json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which the field is stored
-        #' @return NULL
+        #' @return None
         get_integer_vector = function(field_name, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 stopifnot(json_contains_field_cpp(self$json_ptr, field_name))
@@ -297,7 +297,7 @@ CppJson <- R6::R6Class(
         #' Retrieve a character vector from the json object under the name "field_name" (with optional subfolder "subfolder_name")
         #' @param field_name The name of the field to be accessed from json
         #' @param subfolder_name (Optional) Name of the subfolder / hierarchy under which the field is stored
-        #' @return NULL
+        #' @return None
         get_string_vector = function(field_name, subfolder_name = NULL) {
             if (is.null(subfolder_name)) {
                 stopifnot(json_contains_field_cpp(self$json_ptr, field_name))
@@ -313,7 +313,7 @@ CppJson <- R6::R6Class(
         #' Reconstruct a list of numeric vectors from the json object stored under "field_name"
         #' @param field_name The name of the field to be added to json
         #' @param key_names Vector of names of list elements (each of which is a vector)
-        #' @return NULL
+        #' @return None
         get_numeric_list = function(field_name, key_names) {
             output <- list()
             for (i in 1:length(key_names)) {
@@ -327,7 +327,7 @@ CppJson <- R6::R6Class(
         #' Reconstruct a list of string vectors from the json object stored under "field_name"
         #' @param field_name The name of the field to be added to json
         #' @param key_names Vector of names of list elements (each of which is a vector)
-        #' @return NULL
+        #' @return None
         get_string_list = function(field_name, key_names) {
             output <- list()
             for (i in 1:length(key_names)) {
@@ -347,7 +347,7 @@ CppJson <- R6::R6Class(
         #' @description
         #' Save a json object to file
         #' @param filename String of filepath, must end in ".json"
-        #' @return NULL
+        #' @return None
         save_file = function(filename) {
             json_save_file_cpp(self$json_ptr, filename)
         }, 
@@ -355,7 +355,7 @@ CppJson <- R6::R6Class(
         #' @description
         #' Load a json object from file
         #' @param filename String of filepath, must end in ".json"
-        #' @return NULL
+        #' @return None
         load_from_file = function(filename) {
             json_load_file_cpp(self$json_ptr, filename)
         }, 
@@ -363,7 +363,7 @@ CppJson <- R6::R6Class(
         #' @description
         #' Load a json object from string
         #' @param json_string JSON string dump
-        #' @return NULL
+        #' @return None
         load_from_string = function(json_string) {
             json_load_string_cpp(self$json_ptr, json_string)
         }
diff --git a/R/variance.R b/R/variance.R
index f2688b15..32fc9a21 100644
--- a/R/variance.R
+++ b/R/variance.R
@@ -5,6 +5,7 @@
 #' @param rng C++ random number generator
 #' @param a Global variance shape parameter
 #' @param b Global variance scale parameter
+#' @return None
 #' @export
 #' 
 #' @examples
@@ -27,7 +28,7 @@ sampleGlobalErrorVarianceOneIteration <- function(residual, dataset, rng, a, b)
 #' @param rng C++ random number generator
 #' @param a Leaf variance shape parameter
 #' @param b Leaf variance scale parameter
-#'
+#' @return None
 #' @export
 #' 
 #' @examples
diff --git a/man/CppJson.Rd b/man/CppJson.Rd
index 65f1edec..828230f5 100644
--- a/man/CppJson.Rd
+++ b/man/CppJson.Rd
@@ -85,7 +85,7 @@ Convert a forest container to json and add to the current \code{CppJson} object
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -105,7 +105,7 @@ Convert a random effects container to json and add to the current \code{CppJson}
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -129,7 +129,7 @@ Add a scalar to the json object under the name "field_name" (with optional subfo
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -153,7 +153,7 @@ Add a scalar to the json object under the name "field_name" (with optional subfo
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -177,7 +177,7 @@ Add a boolean value to the json object under the name "field_name" (with optiona
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -201,7 +201,7 @@ Add a string value to the json object under the name "field_name" (with optional
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -225,7 +225,7 @@ Add a vector to the json object under the name "field_name" (with optional subfo
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -249,7 +249,7 @@ Add an integer vector to the json object under the name "field_name" (with optio
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -273,7 +273,7 @@ Add an array to the json object under the name "field_name" (with optional subfo
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -295,7 +295,7 @@ Add a list of vectors (as an object map of arrays) to the json object under the
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -317,7 +317,7 @@ Add a list of vectors (as an object map of arrays) to the json object under the
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -339,7 +339,7 @@ Retrieve a scalar value from the json object under the name "field_name" (with o
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -361,7 +361,7 @@ Retrieve a integer value from the json object under the name "field_name" (with
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -383,7 +383,7 @@ Retrieve a boolean value from the json object under the name "field_name" (with
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -405,7 +405,7 @@ Retrieve a string value from the json object under the name "field_name" (with o
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -427,7 +427,7 @@ Retrieve a vector from the json object under the name "field_name" (with optiona
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -449,7 +449,7 @@ Retrieve an integer vector from the json object under the name "field_name" (wit
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -471,7 +471,7 @@ Retrieve a character vector from the json object under the name "field_name" (wi
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -493,7 +493,7 @@ Reconstruct a list of numeric vectors from the json object stored under "field_n
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -515,7 +515,7 @@ Reconstruct a list of string vectors from the json object stored under "field_na
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -548,7 +548,7 @@ Save a json object to file
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -568,7 +568,7 @@ Load a json object from file
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -588,7 +588,7 @@ Load a json object from string
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 }
diff --git a/man/ForestModel.Rd b/man/ForestModel.Rd
index f00d7566..61b688a3 100644
--- a/man/ForestModel.Rd
+++ b/man/ForestModel.Rd
@@ -183,7 +183,7 @@ This function is run after the \code{Outcome} class's \code{update_data} method,
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -203,7 +203,7 @@ Update alpha in the tree prior
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -223,7 +223,7 @@ Update beta in the tree prior
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -243,7 +243,7 @@ Update min_samples_leaf in the tree prior
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -263,7 +263,7 @@ Update max_depth in the tree prior
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 }
diff --git a/man/ForestSamples.Rd b/man/ForestSamples.Rd
index 111b1bd6..d1f01d03 100644
--- a/man/ForestSamples.Rd
+++ b/man/ForestSamples.Rd
@@ -139,7 +139,7 @@ Append to a \code{ForestContainer} object from a json object
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -183,7 +183,7 @@ Append to a \code{ForestContainer} object from a json object
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
diff --git a/man/Outcome.Rd b/man/Outcome.Rd
index 224b84a0..656c8f81 100644
--- a/man/Outcome.Rd
+++ b/man/Outcome.Rd
@@ -78,7 +78,7 @@ Update the current state of the outcome (i.e. partial residual) data by adding t
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -98,7 +98,7 @@ Update the current state of the outcome (i.e. partial residual) data by subtract
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -118,7 +118,7 @@ Update the current state of the outcome (i.e. partial residual) data by replacin
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 }
diff --git a/man/RandomEffectSamples.Rd b/man/RandomEffectSamples.Rd
index 3f0da6b9..ecc6230f 100644
--- a/man/RandomEffectSamples.Rd
+++ b/man/RandomEffectSamples.Rd
@@ -75,7 +75,7 @@ Construct RandomEffectSamples object from other "in-session" R objects
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -137,7 +137,7 @@ Append random effect draws to \code{RandomEffectSamples} object from a json obje
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL (updates object in-place)
+None
 }
 }
 \if{html}{\out{<hr>}}
@@ -199,7 +199,7 @@ Append random effect draws to \code{RandomEffectSamples} object from a json obje
 \if{html}{\out{</div>}}
 }
 \subsection{Returns}{
-NULL (updates object in-place)
+None
 }
 }
 \if{html}{\out{<hr>}}
diff --git a/man/resetActiveForest.Rd b/man/resetActiveForest.Rd
index 832b6502..3f9b1a5a 100644
--- a/man/resetActiveForest.Rd
+++ b/man/resetActiveForest.Rd
@@ -14,6 +14,9 @@ resetActiveForest(active_forest, forest_samples = NULL, forest_num = NULL)
 
 \item{forest_num}{(Optional) Index of forest samples from which to initialize active forest. If not provided, active forest will be reset to an ensemble of single-node (i.e. root) trees.}
 }
+\value{
+None
+}
 \description{
 Reset an active forest, either from a specific forest in a \code{ForestContainer}
 or to an ensemble of single-node (i.e. root) trees
diff --git a/man/resetForestModel.Rd b/man/resetForestModel.Rd
index 10633e03..07f3a8fa 100644
--- a/man/resetForestModel.Rd
+++ b/man/resetForestModel.Rd
@@ -17,6 +17,9 @@ resetForestModel(forest_model, forest, dataset, residual, is_mean_model)
 
 \item{is_mean_model}{Whether the model being updated is a conditional mean model}
 }
+\value{
+None
+}
 \description{
 Re-initialize a forest model (tracking data structures) from a specific forest in a \code{ForestContainer}
 }
diff --git a/man/resetRandomEffectsModel.Rd b/man/resetRandomEffectsModel.Rd
index e42797de..47afb38b 100644
--- a/man/resetRandomEffectsModel.Rd
+++ b/man/resetRandomEffectsModel.Rd
@@ -15,6 +15,9 @@ resetRandomEffectsModel(rfx_model, rfx_samples, sample_num, sigma_alpha_init)
 
 \item{sigma_alpha_init}{Initial value of the "working parameter" scale parameter.}
 }
+\value{
+None
+}
 \description{
 Reset a \code{RandomEffectsModel} object based on the parameters indexed by \code{sample_num} in a \code{RandomEffectsSamples} object
 }
diff --git a/man/resetRandomEffectsTracker.Rd b/man/resetRandomEffectsTracker.Rd
index bae73a66..743978e1 100644
--- a/man/resetRandomEffectsTracker.Rd
+++ b/man/resetRandomEffectsTracker.Rd
@@ -23,6 +23,9 @@ resetRandomEffectsTracker(
 
 \item{rfx_samples}{Object of type \code{RandomEffectSamples}.}
 }
+\value{
+None
+}
 \description{
 Reset a \code{RandomEffectsTracker} object based on the parameters indexed by \code{sample_num} in a \code{RandomEffectsSamples} object
 }
diff --git a/man/rootResetRandomEffectsModel.Rd b/man/rootResetRandomEffectsModel.Rd
index de1b3448..03043fa4 100644
--- a/man/rootResetRandomEffectsModel.Rd
+++ b/man/rootResetRandomEffectsModel.Rd
@@ -29,6 +29,9 @@ rootResetRandomEffectsModel(
 
 \item{sigma_xi_scale}{Scale parameter for the inverse gamma variance model on the group parameters.}
 }
+\value{
+None
+}
 \description{
 Reset a \code{RandomEffectsModel} object to its "default" state
 }
diff --git a/man/rootResetRandomEffectsTracker.Rd b/man/rootResetRandomEffectsTracker.Rd
index 1f3c5461..82893d0e 100644
--- a/man/rootResetRandomEffectsTracker.Rd
+++ b/man/rootResetRandomEffectsTracker.Rd
@@ -15,6 +15,9 @@ rootResetRandomEffectsTracker(rfx_tracker, rfx_model, rfx_dataset, residual)
 
 \item{residual}{Object of type \code{Outcome}.}
 }
+\value{
+None
+}
 \description{
 Reset a \code{RandomEffectsTracker} object to its "default" state
 }
diff --git a/man/sampleGlobalErrorVarianceOneIteration.Rd b/man/sampleGlobalErrorVarianceOneIteration.Rd
index cd8eda75..f2068a13 100644
--- a/man/sampleGlobalErrorVarianceOneIteration.Rd
+++ b/man/sampleGlobalErrorVarianceOneIteration.Rd
@@ -17,6 +17,9 @@ sampleGlobalErrorVarianceOneIteration(residual, dataset, rng, a, b)
 
 \item{b}{Global variance scale parameter}
 }
+\value{
+None
+}
 \description{
 Sample one iteration of the (inverse gamma) global variance model
 }
diff --git a/man/sampleLeafVarianceOneIteration.Rd b/man/sampleLeafVarianceOneIteration.Rd
index b444a726..b79ee84a 100644
--- a/man/sampleLeafVarianceOneIteration.Rd
+++ b/man/sampleLeafVarianceOneIteration.Rd
@@ -15,6 +15,9 @@ sampleLeafVarianceOneIteration(forest, rng, a, b)
 
 \item{b}{Leaf variance scale parameter}
 }
+\value{
+None
+}
 \description{
 Sample one iteration of the leaf parameter variance model (only for univariate basis and constant leaf!)
 }
diff --git a/man/saveBARTModelToJsonFile.Rd b/man/saveBARTModelToJsonFile.Rd
index 869caa44..3b24e210 100644
--- a/man/saveBARTModelToJsonFile.Rd
+++ b/man/saveBARTModelToJsonFile.Rd
@@ -11,6 +11,9 @@ saveBARTModelToJsonFile(object, filename)
 
 \item{filename}{String of filepath, must end in ".json"}
 }
+\value{
+None
+}
 \description{
 Convert the persistent aspects of a BART model to (in-memory) JSON and save to a file
 }
diff --git a/vignettes/EnsembleKernel.Rmd b/vignettes/EnsembleKernel.Rmd
index 2863efe3..9d237db8 100644
--- a/vignettes/EnsembleKernel.Rmd
+++ b/vignettes/EnsembleKernel.Rmd
@@ -102,9 +102,9 @@ bart_model <- bart(X_train=X_train, y_train=y_train, X_test=X_test, mean_forest_
 
 # Extract kernels needed for kriging
 leaf_mat_train <- computeForestLeafIndices(bart_model, X_train, forest_type = "mean", 
-                                           forest_inds = bart_model$model_params$num_samples)
+                                           forest_inds = bart_model$model_params$num_samples - 1)
 leaf_mat_test <- computeForestLeafIndices(bart_model, X_test, forest_type = "mean", 
-                                           forest_inds = bart_model$model_params$num_samples)
+                                           forest_inds = bart_model$model_params$num_samples - 1)
 W_train <- sparseMatrix(i=rep(1:length(y_train),num_trees), j=leaf_mat_train + 1, x=1)
 W_test <- sparseMatrix(i=rep(1:length(y_test),num_trees), j=leaf_mat_test + 1, x=1)
 Sigma_11 <- tcrossprod(W_test) / num_trees
@@ -179,9 +179,9 @@ bart_model <- bart(X_train=X_train, y_train=y_train, X_test=X_test, mean_forest_
 
 # Extract kernels needed for kriging
 leaf_mat_train <- computeForestLeafIndices(bart_model, X_train, forest_type = "mean", 
-                                           forest_inds = bart_model$model_params$num_samples)
+                                           forest_inds = bart_model$model_params$num_samples - 1)
 leaf_mat_test <- computeForestLeafIndices(bart_model, X_test, forest_type = "mean", 
-                                           forest_inds = bart_model$model_params$num_samples)
+                                           forest_inds = bart_model$model_params$num_samples - 1)
 W_train <- sparseMatrix(i=rep(1:length(y_train),num_trees), j=leaf_mat_train + 1, x=1)
 W_test <- sparseMatrix(i=rep(1:length(y_test),num_trees), j=leaf_mat_test + 1, x=1)
 Sigma_11 <- tcrossprod(W_test) / num_trees