In our most recent post, we concluded that New Jersey’s counties are indeed very diverse in terms of household income. Here, we continue our exploration of income diversity in New Jersey by conducting a diversity analysis of New Jersey neighborhoods. This neighborhood-level analysis will help us to understand if, like our counties, our neighborhoods are very diverse (i.e., comprised of more equal shares of households from many of the groups on our income scale), or are more homogeneous (i.e., dominated by large shares of households from one particular or only a few groups on our income scale).
Just as with exploring racial and ethnic diversity, we have conducted this analysis by calculating every neighborhood’s Household Income Diversity Index.[i] In order to understand the diversity of the average neighborhood in each county, we then calculated the Average Neighborhood Household Income Diversity Index for all neighborhoods in each county in the US. This will not only allow us to compare New Jersey counties to each other, but also to all other US counties.
Map 1: Average Neighborhood Household Diversity Index of NJ Counties
Map 1 shows every New Jersey county shaded by which quartile of US counties its Average Neighborhood Diversity Index Score falls into. The most immediately noticeable feature of this map is that it is overwhelmingly yellow and green. Unlike the map in our previous post, which showed the majority of New Jersey counties falling within the top quartile of Countywide Household Income Diversity, this map is showing the diametric contradiction, where the majority of New Jersey counties are falling within the bottom quartile of Average Neighborhood Household Income Diversity. In fact, the same number of New Jersey counties (12, or 57%) fall within the lowest quartile for Average Neighborhood Diversity as did in the highest quartile for Countywide Diversity.
Chart 1, below, shows how far each New Jersey county falls below the mark of the US county with the highest Average Neighborhood Household Income Diversity Index Score, as well as the cut-off points for the top and bottom quartiles of Average Neighborhood Household Income Diversity for all US counties. Looking at the chart, it certainly seems that most New Jersey Counties are fare below the highest US county quartile of Average Neighborhood Household Income Diversity.
The two tables immediately below are shown to provide a glimpse into how New Jersey and its counties dramatically compare with others in the US. Table 1 shows the top and bottom ten states in terms of the proportion of their counties ranked in the highest quartile of Average Neighborhood Household Income Diversity of all US counties. Six states, including New Jersey, do not have any counties that fall within the top quartile of US counties.
Table 2 shows two New Jersey Counties alongside the ten highest-scoring US counties in terms of Average Neighborhood Household Income Diversity Index Scores. New Jersey’s highest scoring county, Cape May County, has an Average Neighborhood Household Income Diversity Index Score of 85.85, good enough to tie for 1,287th place out of all US counties. Essex County, the highest scoring county in all of the US in terms of its Countywide Household Income Diversity Index Score, is tied for 2,963th place out of all 3,142 US counties.
These results suggest that, on average, neighborhoods in New Jersey are very homogeneous in terms of household income earned. This means that individual neighborhoods are more likely to be home to households from only a few of the ten income groups described by the US Census Bureau. As mentioned earlier, this stands in stark diametric contradiction to the fact that New Jersey counties as a whole are considered to be extremely diverse in their household income composition. The fact that such a stark contradiction exists between New Jersey’s counties and the individual neighborhoods within hints at a high degree of segregation. This will be discussed thoroughly in our next post, as we examine the difference between a county’s Average Neighborhood Household Income Diversity Index Score and its Countywide Household Income Diversity Index Score, while also discussing the impact of such differences.
For now, see Table 3, below, to observe the Average Neighborhood Household Income Diversity Index Score of each New Jersey County.
[i] Rather than using census block groups as was done with racial and ethnic diversity, we have used census tracts to define neighborhoods. This was done because, unlike demographic information, there is a greater degree of error in dealing with socioeconomic information, such as income, at geographies below the census tract level.
For a PDF version of this post, click here.
Author: John Manieri, AICP
Research, Analysis, and Technical Assistance: Steve Scott