MCI (version 1.0.1)

var.correct: Correcting MCI input variables

Description

This function corrects a numeric variable to match the MCI standards.

Usage

var.correct(x, incby = 1, auto = FALSE)

Arguments

x

a numeric vector

incby

value to increase the values with (default = 1)

auto

boolean argument (default auto = FALSE) if invalid values are increased automatically by the absolute value of the minimum + incby

Value

• Returns a numeric vector with the corrected values.

Details

In the MCI model, only numeric variables with values greater than zero are accepted (From the theoretical perspective, a zero or negative attractivity/utility is just as impossible as zero or negative market shares. In the log-centering transformation, those values cannot be processed.). This function corrects a numeric variable with zero and/or negative values. The most frequent case is that some market shares are equal to zero and are increased by 1.

References

Colome Perales, R. (2002): Consumer Choice in Competitive Location Models. Barcelona. Hartmann, M. (2005): Gravitationsmodelle als Verfahren der Standortanalyse im Einzelhandel. Statistik Regional Electronic Papers, 02/2005. Halle. Tihi, B./Oruc, N. (2012): Competitive Location Assessment - the MCI Approach. In: South East European Journal of Economics and Business, 7, 2, p. 35-49. Wieland, T. (2015): Raeumliches Einkaufsverhalten und Standortpolitik im Einzelhandel unter Beruecksichtigung von Agglomerationseffekten. Theoretische Erklaerungsansaetze, modellanalytische Zugaenge und eine empirisch-oekonometrische Marktgebietsanalyse anhand eines Fallbeispiels aus dem laendlichen Raum Ostwestfalens/Suedniedersachsens. Geographische Handelsforschung, 23. 289 pages. Mannheim : MetaGIS.

See Also

var.check

Examples

var1 <- c(11, 17.5, 24.1, 0.9, 21.2, 0)
# a vector containg one zero value
var.correct(var1)
# returns a vector with input values increased by 1

var2 <- -5:5
# a vector with zero/negative values
var.correct(var2, auto = TRUE)
# returns a vector with minimum value equal to 1