segregation.aspatial.Isolation

class segregation.aspatial.Isolation(data, group_pop_var, total_pop_var)[source]

Classic Isolation Index

Parameters
dataa pandas DataFrame
group_pop_varstring

The name of variable in data that contains the population size of the group of interest (X)

total_pop_varstring

The name of variable in data that contains the total population of the unit

Notes

The group of interest is labelled as group X.

Based on Massey, Douglas S., and Nancy A. Denton. “The dimensions of residential segregation.” Social forces 67.2 (1988): 281-315.

Reference: [MD88].

Examples

In this example, we will calculate the Isolation Index (xPx) for the Riverside County using the census tract data of 2010. The group of interest is non-hispanic black people which is the variable nhblk10 in the dataset.

Firstly, we need to perform some import the modules and the respective function.

>>> import pandas as pd
>>> import geopandas as gpd
>>> import segregation
>>> from segregation.aspatial import Isolation

Secondly, we need to read the data:

>>> # This example uses all census data that the user must provide your own copy of the external database.
>>> # A step-by-step procedure for downloading the data can be found here: https://github.com/spatialucr/geosnap/blob/master/examples/01_getting_started.ipynb
>>> # After the user download the LTDB_Std_All_fullcount.zip and extract the files, the filepath might be something like presented below.
>>> filepath = '~/data/LTDB_Std_2010_fullcount.csv'
>>> census_2010 = pd.read_csv(filepath, encoding = "ISO-8859-1", sep = ",")

Then, we filter only for the desired county (in this case, Riverside County):

>>> df = census_2010.loc[census_2010.county == "Riverside County"][['pop10','tractid']]

The value is estimated below.

>>> isolation_index = Isolation(df, 'tractid', 'pop10')
>>> isolation_index.statistic
0.11321482777341298

The interpretation of this number is that if you randomly pick a X member of a specific area, there is 11.32% of probability that this member shares a unit with another X member.

Attributes
statisticfloat

Isolation Index

core_dataa pandas DataFrame

A pandas DataFrame that contains the columns used to perform the estimate.

__init__(data, group_pop_var, total_pop_var)[source]

Initialize self. See help(type(self)) for accurate signature.

Methods

__init__(data, group_pop_var, total_pop_var)

Initialize self.