Scenario

New York City faces a seemingly endless housing crunch, particularly where affordable housing is concerned. You are an urban planner working for the Mayor’s Office and have been asked to evaluate the outcomes of various approaches to housing policy put forth by past administrations. Of course, all of these policies have been extensively tracked and studied. (There is no shortage of planning literature on the efficacy and effectiveness of specific housing policies.) Still, many reports opt to describe the development of housing units in citywide (or perhaps borough-level) terms given that policy interventions generally operate across the city, while neighborhood-level outcomes are often determined by the availability of land for development and/or individual rezoning efforts to create more development opportunities. Further, many of the reports you’ve come across provide detailed information and summaries of specific affordability measures but rarely compare the geography of affordable housing development to that of new residential overall (regardless of affordability).

As a starting point for neighborhood-level comparisons, you and your team have decided to map the density of new residential developments across the city during different time periods (corresponding to different mayoral housing policies). Your task is to map the relative density of residential development in Queens corresponding with the decade that followed the Bloomberg administration’s New Housing Marketplace program, which was announced in 2003. The question your map(s) will need to answer, in other words, is

For your reference, you can find a copy of the New Housing Marketplace plan in the \docs\ folder accompanying this exercise. (There are also several evaluations of the policy available online.)

Assignment & Deliverables

Complete the exercise below, answering the embedded questions.

Prepare one map composition no larger than 8.5 inches by 11 inches (portrait orientation) depicting the relative density of new residential units in Queens, at a scale that can describe neighborhood-level variation, built between in 2003 to 2013. The deliverable should primarily depict a kernel density map of residential units in buildings that were built during that time. For reference or comparison, you may want to consider including one or more of the following:

The list above are a few suggestions. Feel free to include additional or different pertinent information and calculations. As always, your map composition should include the minimum necessary elements (scale bar, north arrow, legend, etc).

<aside> ❔ QUESTION 1: (This question should be kept in mind while completing the exercise but should be the last question of this exercise that you answer.) What are the parameters (cell size and search radius) of the kernel density map(s) shown in your deliverable composition? Briefly describe the rationale for your choice.

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Approach

In order to map the density of new residential development by unit in Queens from 2003 to 2013, we will use the City’s MapPLUTO dataset, isolating properties built within that time frame with residential units. We will create and compare kernel density maps with various parameters, as well as a map of the density of these units by neighborhood tabulation area as a reference.

<aside> ⚠️ NOTE: Neighborhood Tabulation Areas (NTAs) are vector polygons often used as approximate boundaries for one or more neighborhoods, which are neither finite nor stable in their delineation. Indeed, these boundaries were not originally created as approximations for neighborhoods, but as areas for which residential development and population change could be forecasted and compared.

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We will map and calculate the density of new residential properties and units per acre by NTA, then explore several kernel density calculations of each. (Keep in mind that the density of development varies greatly across the borough of Queens, from high-rise multi-unit buildings to single-family detached homes.) Beforehand, we will download the necessary data and check (and possibly correct) their coordinate system information in order to prepare them for analysis.

Data

For this exercise, we will download the necessary data from open sources provided by the City. We will need two datasets: the current PLUTO data for the borough of Queens and the Neighborhood Tabulation Area boundaries.