Get enumeration counts from a bus-route creel design with interviews

Returns the enumeration count data (observed and interviewed angler counts, and the expansion factor) for each interview record in a bus-route creel_design with interviews attached via add_interviews.

The expansion factor \(n\_counted / n\_interviewed\) accounts for anglers present at a site who were not interviewed. It is used during bus-route effort and harvest estimation (Jones & Pollock (2012) Eq. 19.4 and 19.5).

Usage

get_enumeration_counts(design)

Arguments

design

A creel_design object with design_type = "bus_route" and interview data attached via add_interviews.

Value

A data frame with the site identifier column, the circuit identifier column, n_counted (resolved column name), n_interviewed (resolved column name), and .expansion (n_counted / n_interviewed, NA when n_interviewed = 0).

References

Jones, C. M., & Pollock, K. H. (2012). Recreational survey methods: estimating effort, harvest, and abundance. In A. V. Zale, D. L. Parrish, & T. M. Sutton (Eds.), Fisheries Techniques (3rd ed., pp. 883–919). American Fisheries Society. Enumeration expansion factor used in Eq. 19.4 and 19.5 for bus-route effort and harvest estimation.

See also

creel_design(), add_interviews(), get_sampling_frame(), get_inclusion_probs()

Other "Bus-Route Helpers": get_inclusion_probs(), get_sampling_frame(), get_site_contributions()

Examples

cal <- data.frame(
  date = as.Date(c("2024-06-03", "2024-06-04", "2024-06-05", "2024-06-06")),
  day_type = "weekday"
)
sf <- data.frame(
  site = c("A", "B"),
  circuit = c("am", "am"),
  p_site = c(0.6, 0.4),
  p_period = rep(0.5, 2)
)
design_br <- creel_design(
  cal,
  date = date, strata = day_type,
  survey_type = "bus_route", sampling_frame = sf,
  site = site, circuit = circuit,
  p_site = p_site, p_period = p_period
)
interviews <- data.frame(
  date = as.Date(c("2024-06-03", "2024-06-04")),
  site = c("A", "B"), circuit = c("am", "am"),
  catch_total = c(3L, 2L), hours_fished = c(2.0, 1.5),
  trip_status = c("complete", "complete"),
  trip_duration = c(2.0, 1.5),
  n_counted = c(5L, 4L), n_interviewed = c(3L, 2L)
)
design2 <- add_interviews(
  design_br, interviews,
  catch = catch_total, effort = hours_fished,
  trip_status = trip_status, trip_duration = trip_duration,
  n_counted = n_counted, n_interviewed = n_interviewed
)
#> ℹ No `n_anglers` provided — assuming 1 angler per interview.
#> ℹ Pass `n_anglers = <column>` to use actual party sizes for angler-hour
#>   normalization.
#> Warning: 1 stratum has fewer than 3 interviews:
#> • Stratum weekday: 2 interviews
#> ! Sparse strata produce unstable variance estimates.
#> ℹ Consider combining sparse strata or collecting more data.
#> ℹ Added 2 interviews: 2 complete (100%), 0 incomplete (0%)
get_enumeration_counts(design2)
#>   site circuit n_counted n_interviewed .expansion
#> 1    A      am         5             3   1.666667
#> 2    B      am         4             2   2.000000