Define choice identifiers

The choice_identifiers object defines identifiers for the deciders and choice occasions.

• generate_choice_identifiers() generates identifiers.

• extract_choice_identifiers() extracts choice identifiers.

Usage

choice_identifiers(
  data_frame,
  format = "wide",
  column_decider = "deciderID",
  column_occasion = "occasionID",
  cross_section = FALSE
)

generate_choice_identifiers(
  N = length(Tp),
  Tp = 1,
  column_decider = "deciderID",
  column_occasion = "occasionID"
)

extract_choice_identifiers(
  x,
  format = attr(x, "format"),
  column_decider = attr(x, "column_decider"),
  column_occasion = attr(x, "column_occasion"),
  cross_section = attr(x, "cross_section")
)

Arguments

data_frame

[data.frame]
Contains the choice identifiers.

format

[character(1)]
Either "wide" or "long".

In the long case, unique combinations of column_decider and column_occasion (if present) are used.

column_decider

[character(1)]
The name of the identifier column for deciders.

column_occasion

[character(1) | NULL]
The name of the identifier column for choice occasions (panel data). Can be NULL for the cross-sectional case.

cross_section

[logical(1)]
Treat choice data as cross-sectional?

N

[integer(1)]
The number of deciders.

Tp

[integer(1) | integer(N)]
The number of choice occasions per decider.

Can also be of length N for a variable number of choice occasions per decider.

x

An object of class

• choice_data,

• choice_covariates, containing the identifiers and covariate values for each decider, occasion, and alternative,

Value

An object of class choice_identifiers, which is a tibble with columns:

1. column_decider contains the decider identifiers,

2. column_occasion contains the choice occasion identifiers (only if column_occasion is not NULL and cross_section = FALSE).

Examples

### panel case
generate_choice_identifiers(N = 2, Tp = 2)
#> # A tibble: 4 × 2
#>   deciderID occasionID
#> * <chr>     <chr>     
#> 1 1         1         
#> 2 1         2         
#> 3 2         1         
#> 4 2         2         

### cross-sectional case
generate_choice_identifiers(N = 5, column_occasion = NULL)
#> # A tibble: 5 × 1
#>   deciderID
#> * <chr>    
#> 1 1        
#> 2 2        
#> 3 3        
#> 4 4        
#> 5 5        

### read choice identifiers
choice_identifiers(
  data_frame = travel_mode_choice,
  format = "long",
  column_decider = "individual",
  column_occasion = NULL,
  cross_section = TRUE
)
#> # A tibble: 210 × 1
#>    individual
#>  * <chr>     
#>  1 1         
#>  2 2         
#>  3 3         
#>  4 4         
#>  5 5         
#>  6 6         
#>  7 7         
#>  8 8         
#>  9 9         
#> 10 10        
#> # ℹ 200 more rows