Accessibility

How do POPS vary in access?

definition

We examined gravity access reflected in walking distance to POPS and parks for different income groups, modeled as a curve in which desire to walk declines at a non-linear rate.

hypothesis

We hypothesize that parks will be more accessible to low income groups than POPS, which are predominantly located in Manhattan and gentrified parts of Brooklyn. POPS and parks may have similar access to medium and high income groups.

method

We mapped all privately owned public spaces (POPS) in New York City in Rhino. We then ran gravity analysis using the Urban Network Analysis (UNA) plugin created for Rhino by the Harvard Graduate School of Design's City Form Lab. The gravity analysis used populations counts from each census block group as origins and measured the walking access to each POPS or park, accounting for a decay rate (beta) of 0.004. We then separated the median income from each block group into four income ranges and found the average gravity access for each income range.

Access to POPS and parks differs by income level. Our analysis reveals that access to POPS and Parks differs greatly between income levels with higher levels of POPS access for the highest income quartile and high access to parks among the lowest income quartile.

Higher income census blocks have significantly greater access to POPS. The highest quartile has 7 times higher accessibility to POPS than the quartile below it, and 68 times higher accessibility than the lowest income group. This relationship has been tested to fit exponentially.

Access to parks did not differ significantly across income groups. Parks and income income groups a different correlation with the highest and lowest quartiles having similar access compared to the middle income groups. However, an ANOVA test reveals no significant difference of average gravity to parks across income levels.

Access to parks varied within income groups. Although the low income level has the highest average gravity value to Parks, there is a significant heterogeneity of accessibility within that group.

Takeways

POPS

Gravity access to POPS is significantly higher for high income groups.

High Access

Low Access