model_aggregate: Hierarchical aggregation via model specification

In SSBtools: Statistics Norway's Miscellaneous Tools

Hierarchical aggregation via model specification

Description

Internally a dummy/model matrix is created according to the model specification. This model matrix is used in the aggregation process via matrix multiplication and/or the function aggregate_multiple_fun.

Usage

model_aggregate(
  data,
  sum_vars = NULL,
  fun_vars = NULL,
  fun = NULL,
  hierarchies = NULL,
  formula = NULL,
  dim_var = NULL,
  remove_empty = NULL,
  preagg_var = NULL,
  dummy = TRUE,
  pre_aggregate = dummy,
  list_return = FALSE,
  pre_return = FALSE,
  verbose = TRUE,
  mm_args = NULL,
  ...
)

Arguments

data	A data frame containing data to be aggregated
sum_vars	Variables to be summed. This will be done via matrix multiplication.
fun_vars	Variables to be aggregated by supplied functions. This will be done via aggregate_multiple_fun and dummy_aggregate and fun_vars is specified as the parameter vars.
fun	The fun parameter to aggregate_multiple_fun
hierarchies	The hierarchies parameter to ModelMatrix
formula	The formula parameter to ModelMatrix
dim_var	The dimVar parameter to ModelMatrix
remove_empty	When non-NULL, the removeEmpty parameter to ModelMatrix. Thus, the actual default value is TRUE with formula input without hierarchy and otherwise FALSE (see ModelMatrix).
preagg_var	Extra variables to be used as grouping elements in the pre-aggregate step
dummy	The dummy parameter to dummy_aggregate. When TRUE, only 0s and 1s are assumed in the generated model matrix. When FALSE, non-0s in this matrix are passed as an additional first input parameter to the fun functions.
pre_aggregate	Whether to pre-aggregate data to reduce the dimension of the model matrix. Note that all original fun_vars observations are retained in the aggregated dataset and pre_aggregate does not affect the final result. However, pre_aggregate must be set to FALSE when the dummy_aggregate parameter dummy is set to FALSE since then unlist will not be run. An exception to this is if the fun functions are written to handle list data.
list_return	Whether to return a list of separate components including the model matrix x.
pre_return	Whether to return the pre-aggregate data as a two-component list. Can also be combined with list_return (see examples).
verbose	Whether to print information during calculations.
mm_args	List of further arguments passed to ModelMatrix.
...	Further arguments passed to dummy_aggregate.

Details

With formula input, limited output can be achieved by formula_selection (see example). An attribute called startCol has been added to the output data frame to make this functionality work.

Value

A data frame or a list.

Examples

z <- SSBtoolsData("sprt_emp_withEU")
z$age[z$age == "Y15-29"] <- "young"
z$age[z$age == "Y30-64"] <- "old"
names(z)[names(z) == "ths_per"] <- "ths"
z$y <- 1:18

my_range <- function(x) c(min = min(x), max = max(x))

out <- model_aggregate(z, 
   formula = ~age:year + geo, 
   sum_vars = c("y", "ths"), 
   fun_vars = c(sum = "ths", mean = "y", med = "y", ra = "ths"), 
   fun = c(sum = sum, mean = mean, med = median, ra = my_range))

out

# Limited output can be achieved by formula_selection
formula_selection(out, ~geo)


# Using the single unnamed variable feature.
model_aggregate(z, formula = ~age, fun_vars = "y", 
                fun = c(sum = sum, mean = mean, med = median, n = length))


# To illustrate list_return and pre_return 
for (pre_return in c(FALSE, TRUE)) for (list_return in c(FALSE, TRUE)) {
  cat("\n=======================================\n")
  cat("list_return =", list_return, ", pre_return =", pre_return, "\n\n")
  out <- model_aggregate(z, formula = ~age:year, 
                         sum_vars = c("ths", "y"), 
                         fun_vars = c(mean = "y", ra = "y"), 
                         fun = c(mean = mean, ra = my_range), 
                         list_return = list_return,
                         pre_return = pre_return)
  cat("\n")
  print(out)
}


# To illustrate preagg_var 
model_aggregate(z, formula = ~age:year, 
sum_vars = c("ths", "y"), 
fun_vars = c(mean = "y", ra = "y"), 
fun = c(mean = mean, ra = my_range), 
preagg_var = "eu",
pre_return = TRUE)[["pre_data"]]


# To illustrate hierarchies 
geo_hier <- SSBtoolsData("sprt_emp_geoHier")
model_aggregate(z, hierarchies = list(age = "All", geo = geo_hier), 
                sum_vars = "y", 
                fun_vars = c(sum = "y"))

####  Special non-dummy cases illustrated below  ####

# Extend the hierarchy to make non-dummy model matrix  
geo_hier2 <- rbind(data.frame(mapsFrom = c("EU", "Spain"), 
                              mapsTo = "EUandSpain", sign = 1), geo_hier[, -4])

# Warning since non-dummy
# y and y_sum are different 
model_aggregate(z, hierarchies = list(age = "All", geo = geo_hier2), 
                sum_vars = "y", 
                fun_vars = c(sum = "y"))

# No warning since dummy since unionComplement = TRUE (see ?HierarchyCompute)
# y and y_sum are equal   
model_aggregate(z, hierarchies = list(age = "All", geo = geo_hier2), 
                sum_vars = "y", 
                fun_vars = c(sum = "y"),
                mm_args = list(unionComplement = TRUE))

# Non-dummy again, but no warning since dummy = FALSE
# Then pre_aggregate is by default set to FALSE (error when TRUE) 
# fun with extra argument needed (see ?dummy_aggregate)
# y and y_sum2 are equal
model_aggregate(z, hierarchies = list(age = "All", geo = geo_hier2), 
                sum_vars = "y", 
                fun_vars = c(sum2 = "y"),
                fun = c(sum2 = function(x, y) sum(x * y)),
                dummy = FALSE) 
                

SSBtools documentation built on Oct. 30, 2024, 5:09 p.m.