sim_data_N: Simulate biased (via over-dispersion in N) point count and...

Description Usage Arguments Value Examples

View source: R/sim_data_N.R

Description

Generate point counts and/or distance sampling data that is biased by over-dispersion in the true abundance, N. Distance sampling data is created with each dataset, but it can just be ignored if you only want the point count data. This is a rudementary function. Currently it assumes constant density, detection probability, transects length, etc.

Usage

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sim_data_N(
  n_sites = 50,
  n_samps = 6,
  lambda1 = 5,
  lambda2 = 5,
  det_prob = 0.42,
  sigma = NA,
  W = 20
)

Arguments

n_sites

number of sites (transects)

n_samps

number of samples (replicates) per site

lambda1

partial mean abundance at every site (single draw per site that stays constant across samples)

lambda2

partial mean abundance at every replicate (new draw for every sample at every site)

det_prob

mean detection probability

sigma

detection parameter (meters). Just leave this blank and it will be calculated from det_prob

W

transect half-width (meters)

Value

Returns a list of 4 items: 1. "true_N" is a matrix of true abundance values for each site (row) and sample (column). 2. "n_obs" is a matrix of the number of observed organisms at each site (row) and sample (column). 3. "y_list" is a list of vectors. Each vector holds the distance data for a single survey. 4. "inputs" is a list of input values.

Examples

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philipshirk/nmmsims documentation built on Feb. 26, 2020, 11:27 a.m.