# ubiquity: Compute a simple measure of ubiquity of industries In PABalland/EconGeo: Computing Key Indicators of the Spatial Distribution of Economic Activities

## Description

This function computes a simple measure of ubiquity of industries by counting the number of regions in which an industry can be found (location quotient > 1) from regions - industries (incidence) matrices

## Usage

 `1` ```ubiquity(mat, RCA = FALSE) ```

## Arguments

 `mat` An incidence matrix with regions in rows and industries in columns `RCA` Logical; should the index of relative comparative advantage (RCA - also refered to as location quotient) first be computed? Defaults to FALSE (a binary matrix - 0/1 - is expected as an input), but can be set to TRUE if the index of relative comparative advantage first needs to be computed

## Author(s)

Pierre-Alexandre Balland p.balland@uu.nl

## References

Balland, P.A. and Rigby, D. (2017) The Geography of Complex Knowledge, Economic Geography 93 (1): 1-23.

`diversity` `location.quotient`
 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17``` ```## generate a region - industry matrix with full count set.seed(31) mat <- matrix(sample(0:10,20,replace=T), ncol = 4) rownames(mat) <- c ("R1", "R2", "R3", "R4", "R5") colnames(mat) <- c ("I1", "I2", "I3", "I4") ## run the function ubiquity (mat, RCA = TRUE) ## 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=T), ncol = 4) rownames(mat) <- c ("R1", "R2", "R3", "R4", "R5") colnames(mat) <- c ("I1", "I2", "I3", "I4") ## run the function ubiquity (mat) ```