createGrid: Create grid for predictions

In lfpdroubi/appraiseR: R Package For Real Estate Appraisals

Create grid for predictions

Description

createGrid create grids to predictions for ploting model variables (terms) with or without confidence/prediction intervals

Usage

createGrid(x, object, at, ...)

Arguments

object	object of class lm
at	List to be used to calculate the predictions (defaults for center of each variable).
...	further arguments passed to predict.lm.
variable	variable to be plotted against response variable
func	function used to transform the response (optional)
interval	the type of interval calculation (provided to predict.lm) to be ploted.
level	Tolerance/confidence level (provided to predict.lm) to be ploted.
ca	(T/F) should the limits of the invertal of arbitration be plotted?
av	(T/F) should the arbitrated value be plotted?

Examples

# Crete random bivariate normal data just for testing
library(MASS)
sample_mean <- c(10000, 250)
sample_cov <- matrix(c(1000^2, -37500,
                       -37500, 50^2),
                     ncol = 2, byrow = T)
n <- 10
set.seed(1)
dados <- mvrnorm(n = n,
                mu = sample_mean,
                Sigma = sample_cov)
colnames(dados) <- c("VU", "Area")
dados <- as.data.frame(dados)

fit <- lm(VU ~ Area, data = dados)
createGrid("Area", fit)
#
# Test with real data
library(sf)
data(centro_2015)
centro_2015 <- within(centro_2015, VU <- valor/area_total)
fit <- lm(sqrt(VU) ~ sqrt(area_total) + quartos + suites + garagens +
          sqrt(dist_b_mar) + padrao,
          data = centro_2015)
createGrid("area_total", fit)
createGrid("area_total", fit,
           at = list(area_total = 205, quartos = 3, suites = 1,
                     garagens = 2, dist_b_mar = 250, padrao = "medio"))

lfpdroubi/appraiseR documentation built on April 14, 2024, 10:27 p.m.