Returns the computed inclusion probabilities (\(\pi_i = p_{\text{site}} \times p_{\text{period}}\)) for each site-circuit combination in a bus-route creel design. The inclusion probability represents the two-stage sampling probability: the probability that a particular site is visited during a particular sampling period, combining both the site selection probability within the circuit and the circuit (period) selection probability.
Arguments
- design
A
creel_design()object created withsurvey_type = "bus_route".
Value
A data frame with three columns: the site identifier column, the
circuit identifier column, and .pi_i (the computed inclusion
probability \(\pi_i = p_{\text{site}} \times p_{\text{period}}\) for
each site-circuit unit). Column names for site and circuit match the
resolved column names from the original sampling frame (or .circuit
for designs without an explicit circuit column).
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. Definition of \(\pi_i\) for two-stage bus-route sampling, used in Eq. 19.4 and 19.5.
See also
creel_design(), get_sampling_frame()
Other "Bus-Route Helpers":
get_enumeration_counts(),
get_sampling_frame(),
get_site_contributions()
Examples
sf <- data.frame(
site = c("A", "B", "C"),
p_site = c(0.3, 0.4, 0.3),
p_period = rep(0.5, 3),
stringsAsFactors = FALSE
)
cal <- data.frame(
date = as.Date("2024-06-01"),
day_type = "weekday",
stringsAsFactors = FALSE
)
design <- creel_design(cal,
date = date, strata = day_type,
survey_type = "bus_route", sampling_frame = sf,
site = site, p_site = p_site, p_period = p_period
)
get_inclusion_probs(design)
#> site .circuit .pi_i
#> 1 A .default 0.15
#> 2 B .default 0.20
#> 3 C .default 0.15