Learn R Programming

siland (version 1.4.6)

Bsiland: Estimation of landscape influence with buffers

Description

Bsiland is used to find the buffer size to estimate lanbdscape influence.

Usage

Bsiland(formula, land, data, family = "gaussian", init = 200, border = F)

Arguments

formula

a symbolic description (see lm() or glm()) of the response variable concerning local variables. Random effects are also allowed according to the syntax in package lme4 (see lmer() function in package lme4).

land

an object of class sf that gives the landscape variables for the model.

data

a dataframe containing the response variable and the local variables.

family

the distribution of response variable. family can be "gaussian", "poisson" or "binomial" and the associated link function are identity, log and logit respectively.

init

a vector indicating the starting values to estimate the buffer sizes. By default, buffer sizes are initialized to 200 for each variable.

border

a logical indicating whereas the buffer are computed from the observation locations (border=F) or from the border of the polygon where observations are located (border=T)

Value

Fsiland returns an object of type list.

coefficients

vector of estimated coefficients

parambuffer

vector of estimated buffer distances

formula

an object of class formula that indicates the local model used

buffer

a dataframe with percentage for each landscape variable inside buffers

loglik

log-likelihood for the estimated parameters

loglik0

log-likelihood for the local model

fitted

fitted values

resoptim

an object of class optim or optimize giving informations about the optimization procedure see optim() or optimize() for further details.

result

an object of type lm/glm/lmer that corresponds to the estimated model conditionnaly to the best buffer sizes for the landscape variables.

AIC

akaike information criterion

AIC0

akaike information criterion for local model (no landscape variable)

nparam

number of parameters

pval0

p.value of the test of global effect of spatial variables. Obtained from the likelihood ratio test between the complete model and the local model.

family

family distribution for the model

sd.error

standard error for gaussian family, NA in other case

model.Type

type of local model: GLM for generalised model, LMM for linear mixed model or GLMM for generalised linear mixed model

rand.StdDev

standard deviation of random effects for LMM or GLMM

err

estimated residuals

newdata

a dataframe with the local variables and the percentages for the different landscape variables obtained with the best buffer sizes.

border

a logical indicating the value used for estimation

Examples

Run this code
# NOT RUN {
data(dataSiland)
data(landSiland)
resB=Bsiland(obs~x1+L1+L2,land=landSiland,data=dataSiland,init = c(50))
resB
summary(resB)
Bsiland.lik(resB,land=landSiland,data=dataSiland,varnames=c("L1","L2"),seqd=seq(50,1000,length=20))


# }
# NOT RUN {
# }

Run the code above in your browser using DataLab