relatedness_density_int_avg {EconGeo}

Compute the average relatedness density within the regional portfolio from regions - industries matrices and industries - industries matrices

Description

This function computes the average relatedness density within the regional portfolio from regions - industries (incidence) matrices and industries - industries (adjacency) matrices. This is a measure of the technological coherence of the regional industrial structure.

Usage

relatedness_density_int_avg(mat, relatedness)

Arguments

mat

An incidence matrix with regions in rows and industries in columns

relatedness

An adjacency industry - industry matrix indicating the degree of relatedness between industries

Value

A vector representing the average relatedness density within the regional portfolio. The values in the vector indicate the average relatedness density for each region, scaled from 0 to 100.

Author(s)

Pierre-Alexandre Balland [e-mail]

References

Boschma, R., Balland, P.A. and Kogler, D. (2015) Relatedness and Technological Change in Cities: The rise and fall of technological knowledge in U.S. metropolitan areas from 1981 to 2010, Industrial and Corporate Change 24 (1): 223-250

Balland P.A., Rigby, D., and Boschma, R. (2015) The Technological Resilience of U.S. Cities, Cambridge Journal of Regions, Economy and Society, 8 (2): 167-184

See Also

relatedness, relatedness_density, relatedness_density_ext, relatedness_density_int, relatedness_density_ext_avg,

Examples

## generate a region - industry matrix in which cells represent the presence/absence
## of a RCA
set.seed(31)
mat <- matrix(sample(0:1, 20, replace = TRUE), ncol = 4)
rownames(mat) <- c("R1", "R2", "R3", "R4", "R5")
colnames(mat) <- c("I1", "I2", "I3", "I4")

## generate an industry - industry matrix in which cells indicate if two industries are
## related (1) or not (0)
relatedness <- matrix(sample(0:1, 16, replace = TRUE), ncol = 4)
relatedness[lower.tri(relatedness, diag = TRUE)] <- t(relatedness)[lower.tri(t(relatedness),
  diag = TRUE
)]
rownames(relatedness) <- c("I1", "I2", "I3", "I4")
colnames(relatedness) <- c("I1", "I2", "I3", "I4")

## run the function
relatedness_density_int_avg(mat, relatedness)