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Grassland vegetation-cover panel (synthetic)

Source: R/datasets.R
meadow_cover.Rd

A vegetation cover-hurdle dataset for 150 grassland plots surveyed across three years, drawn from a known generative model: the species occurs with a probability driven by moisture, and where it occurs, its conditional cover (a Beta-distributed proportion in (0, 1)) increases with moisture and decreases with grazing. Roughly half the plots record zero cover. year_c is the centred survey year, so within_between() can split the cross-plot baseline from the within-plot temporal deviation. Synthetic, not field data; the generative coefficients are attached as attr(meadow_cover, "truth").

Usage

meadow_cover

Format

A data frame with 150 rows (one per plot) and columns:

plot

Plot identifier (factor).

year

Survey year (2018-2020).

year_c

Survey year centred on its mean.

moisture

Standardised soil-moisture index.

grazing

Standardised grazing-pressure index.

cover

Recorded cover as a proportion in [0, 1] (0 where absent).

See also

cover(), tobs(), within_between(), simulate_cover()

Examples

data(meadow_cover)
mean(meadow_cover$cover > 0)
# \donttest{
fit <- tobs(cover ~ moisture, data = meadow_cover,
            family = cover(response = "beta"))
coef(fit)
# }