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Analyse a two-phase allocation

Source: R/print.R
summary.svyplan_twophase.Rd

print() on a n_twophase() result gives the design as it would be fielded: the two phase sizes in whole units, the precision and cost they buy, the per-stratum subsampling fractions, and which of the two designs to run. summary() gives what that answer was chosen against: the continuous optimum beside the fielded one, the full stratum table including the continuous issue, the single-phase comparator with its cost and whether it reaches the target, and the planning assumptions.

Usage

# S3 method for class 'svyplan_twophase'
summary(object, ...)

# S3 method for class 'summary.svyplan_twophase'
print(x, ...)

Arguments

object

A svyplan_twophase object.

...

Additional arguments are not supported and produce an error.

x

A summary.svyplan_twophase object.

Value

summary() returns an object of class summary.svyplan_twophase; its print() method returns it invisibly.

See also

n_twophase() for the planner, and print.svyplan for the printed block this expands on.

Examples

frame <- data.frame(
  stratum   = c("A", "B", "C", "D"),
  N         = c(3500, 2500, 2500, 1500),
  sd        = c(12, 25, 8, 40),
  mean      = c(40, 70, 35, 90),
  unit_cost = c(2, 5, 1, 9)
)
plan <- n_twophase(frame, phase1_cost = 1, budget = 50000)
plan
#> Two-phase allocation (4 phase-2 strata)
#> field design: n_phase1 = 16924 | n_phase2 = 8094
#> cv = 0.0050, cost = 50000
#> 
#>  stratum share    sd unit_cost     nu n_int
#>        A 0.350 12.00      2.00 0.4154  2462
#>        B 0.250 25.00      5.00 0.5474  2316
#>        C 0.250  8.00      1.00 0.3917  1659
#>        D 0.150 40.00      9.00 0.6528  1657
#> 
#> single-phase is better here: n = 14085 at cv 0.0046, so skip phase 1
#> # summary() for the continuous optimum and the comparator
summary(plan)
#> Analysis of a two-phase allocation (4 phase-2 strata)
#> 
#> field design: n_phase1 = 16924 | n_phase2 = 8094
#> cv = 0.0050, cost = 50000
#> continuous optimum: n_phase1 = 16925 | n_phase2 = 8092 (cv 0.0050, cost 50000)
#> 
#> Strata
#>  stratum share    sd unit_cost     nu n_issued n_int
#>        A 0.350 12.00      2.00 0.4154     2461  2462
#>        B 0.250 25.00      5.00 0.5474     2316  2316
#>        C 0.250  8.00      1.00 0.3917     1657  1659
#>        D 0.150 40.00      9.00 0.6528     1657  1657
#> 
#> Single-phase comparator: n = 14085, cv = 0.0046, cost = 50000
#> It is the better design here, and it reaches the target
summary(plan)$detail
#>   stratum share    sd unit_cost     nu n_issued n_int
#> 1       A 0.350 12.00      2.00 0.4154     2461  2462
#> 2       B 0.250 25.00      5.00 0.5474     2316  2316
#> 3       C 0.250  8.00      1.00 0.3917     1657  1659
#> 4       D 0.150 40.00      9.00 0.6528     1657  1657