6. About our data

The data for this workshop is four shapefiles for New York City, and one attribute table of sociodemographic variables. We've loaded our shapefiles as PostGIS tables and will add sociodemographic data later in the workshop.

The following describes the number of records and table attributes for each of our datasets. These attribute values and relationships are fundamental to our future analysis.

To explore the nature of your tables in pgAdmin, right-click a highlighted table and select Properties. You will find a summary of table properties, including a list of table attributes within the Columns tab.

6.1. nyc_census_blocks

A census block is the smallest geography for which census data is reported. All higher level census geographies (block groups, tracts, metro areas, counties, etc) can be built from unions of census blocks. We have attached some demographic data to our collection of blocks.

Number of records: 36592

blkid

A 15-digit code that uniquely identifies every census block. Eg: 360050001009000

popn_total

Total number of people in the census block

popn_white

Number of people self-identifying as "White" in the block

popn_black

Number of people self-identifying as "Black" in the block

popn_nativ

Number of people self-identifying as "Native American" in the block

popn_asian

Number of people self-identifying as "Asian" in the block

popn_other

Number of people self-identifying with other categories in the block

boroname

Name of the New York borough. Manhattan, The Bronx, Brooklyn, Staten Island, Queens

geom

Polygon boundary of the block

_images/nyc_census_blocks.png

Black population as a percentage of Total Population

注解

To get census data into GIS, you need to join two pieces of information: the actual data (text), and the boundary files (spatial). There are many options for getting the data, including downloading data and boundaries from the Census Bureau's American FactFinder.

6.2. nyc_neighborhoods

New York has a rich history of neighborhood names and extent. Neighborhoods are social constructs that do not follow lines laid down by the government. For example, the Brooklyn neighborhoods of Carroll Gardens, Red Hook, and Cobble Hill were once collectively known as "South Brooklyn." And now, depending on which real estate agent you talk to, the same four blocks in the-neighborhood-formerly-known-as-Red-Hook can be referred to as Columbia Heights, Carroll Gardens West, or Red Hook!

Number of records: 129

name

Name of the neighborhood

boroname

Name of the New York borough. Manhattan, The Bronx, Brooklyn, Staten Island, Queens

geom

Polygon boundary of the neighborhood

_images/nyc_neighborhoods.png

The neighborhoods of New York City

6.3. nyc_streets

The street centerlines form the transportation network of the city. These streets have been flagged with types in order to distinguish between such thoroughfares as back alleys, arterial streets, freeways, and smaller streets. Desirable areas to live might be on residential streets rather than next to a freeway.

Number of records: 19091

name

Name of the street

oneway

Is the street one-way? "yes" = yes, "" = no

type

Road type (primary, secondary, residential, motorway)

geom

Linear centerline of the street

_images/nyc_streets.png

The streets of New York City. Major roads are in red.

6.4. nyc_subway_stations

The subway stations link the upper world where people live to the invisible network of subways beneath. As portals to the public transportation system, station locations help determine how easy it is for different people to enter the subway system.

Number of records: 491

name

Name of the station

borough

Name of the New York borough. Manhattan, The Bronx, Brooklyn, Staten Island, Queens

routes

Subway lines that run through this station

transfers

Lines you can transfer to via this station

express

Stations where express trains stop, "express" = yes, "" = no

geom

Point location of the station

_images/nyc_subway_stations.png

Point locations for New York City subway stations

6.5. nyc_census_sociodata

There is a rich collection of social-economic data collected during the census process, but only at the larger geography level of census tract. Census blocks combine to form census tracts (and block groups). We have collected some social-economic at a census tract level to answer some of these more interesting questions about New York City.

注解

The nyc_census_sociodata is a data table. We will need to connect it to Census geographies before conducting any spatial analysis.

tractid

An 11-digit code that uniquely identifies every census tract. ("36005000100")

transit_total

Number of workers in the tract

transit_private

Number of workers in the tract who use private automobiles / motorcycles

transit_public

Number of workers in the tract who take public transit

transit_walk

Number of workers in the tract who walk

transit_other

Number of workers in the tract who use other forms like walking / biking

transit_none

Number of workers in the tract who work from home

transit_time_mins

Total number of minutes spent in transit by all workers in the tract (minutes)

family_count

Number of families in the tract

family_income_median

Median family income in the tract (dollars)

family_income_mean

Average family income in the tract (dollars)

family_income_aggregate

Total income of all families in the tract (dollars)

edu_total

Number of people with educational history

edu_no_highschool_dipl

Number of people with no high school diploma

edu_highschool_dipl

Number of people with high school diploma and no further education

edu_college_dipl

Number of people with college diploma and no further education

edu_graduate_dipl

Number of people with graduate school diploma