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Introduction to Opportunity Mapping. OPPORTUNITY MAPPING WORKSHOP Nov. 30, 2007 Samir Gambhir GIS/Demographic Specialist. Presentation overview. SECTION I – Introduction SECTION II – Methodology SECTION III – Data and analysis SECTION IV – Future possibilities. Section I introduction.
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Introduction to Opportunity Mapping OPPORTUNITY MAPPING WORKSHOP Nov. 30, 2007 Samir Gambhir GIS/Demographic Specialist
Presentation overview • SECTION I – Introduction • SECTION II – Methodology • SECTION III – Data and analysis • SECTION IV – Future possibilities
The “community of opportunity” approach • Where you live is more important than what you live in… • Housing -- in particular its location -- is the primary mechanism for accessing opportunity in our society • Housing location determines • the quality of schools children attend, • the quality of public services they receive, • access to employment and transportation, • exposure to health risks, • access to health care, etc. • For those living in high poverty neighborhoods, these factors can significantly inhibit life outcomes
Fiscal Policies Health Childcare Employment Housing Effective Participation Education Transportation Opportunity structures
framework • The “Communities of Opportunity” framework is a model of fair housing and community development • The model is based on the premises that • Everyone should have fair access to the critical opportunity structures needed to succeed in life • Affirmatively connecting people to opportunity creates positive, transformative change in communities
The web of opportunity • Opportunities in our society are geographically distributed (and often clustered) throughout metropolitan areas • This creates “winner” and “loser” communities or “high” and “low” opportunity communities • Your location within this “web of opportunity” plays a decisive role in your life potential and outcomes • Individual characteristics still matter… • …but so does access to opportunity, such as good schools, health care, child care, and job networks
Opportunity mapping • Opportunity mapping is a research tool used to understand the dynamics of “opportunity” within metropolitan areas • The purpose of opportunity mapping is to illustrate where opportunity rich communities exist (and assess who has access to these communities) • Also, to understand what needs to be remedied in opportunity poor communities
background • Evolved out of neighborhood indicators project • One of the major applications at Kirwan Institute was Chicago MSA opportunity classification (in collaboration with Institute on Race and Poverty, University of Minnesota
background (contd.) • Neighborhood Indicators • Census 2000 data provided detailed neighborhood indicators • Resulted in surge in neighborhood indicators based analysis • Provided a snapshot of social and economic health of neighborhoods • Shortcomings • Each indicator is analyzed and mapped separately • Overlay provides a complex view, hard to interpret
background (contd.) • Opportunity mapping intended to provide a comprehensive view of any number of indicators
background (contd.) • Resulted in a methodology that captures region wide opportunity distribution, in a comprehensive manner and it is reflective of today’s metropolitan characteristics • Ignores Urban-Suburban dichotomy • Reflective of new trends: decline of the inner suburbs, exurbs, inner city gentrification • Reflective of the unique nature of each community: e.g. Austin, TX vs. Cleveland, OH
Methodology • Identifying and selecting indicators of opportunity • Identifying sources of data • Compiling list of indicators (data matrix) • Calculating Z scores • Averaging these scores
Methodology:Identifying and Selecting Indicators of High and Low Opportunity • Established by input from Kirwan Institute and direction from the local steering committee • Based on certain factors • Specific issues or concerns of the region • Research literature validating the connection between indicator and opportunity • Central Requirement: • Is there a clear connection between indicator and opportunity? E.g. Proximity to parks and Health related opportunity
Methodology:Sources of Data • Federal Organizations • Census Bureau • County Business Patterns (ZIP Code Data) • Housing and Urban Development (HUD) • Environmental Protection Agency (EPA) • State and Local Governmental Organizations • Regional planning agencies • Education boards/school districts • Transportation agencies • County Auditor’s Office • Other agencies (non-Profit and Private) • Schoolmatters.org • DataPlace.org • ESRI Business Analyst • Claritas
Methodology:Indicator Categories • Education • Student/Teacher ratio? Test scores? Student mobility? • Economic/Employment Indicators • Unemployment rate? Proximity to employment? Job creation? • Neighborhood Quality • Median home values? Crime rate? Housing vacancy rate? • Mobility/Transportation Indicators • Mean commute time? Access to public transit? • Health & Environmental Indicators • Access to health care? Exposure to toxic waste? Proximity to parks or open space?
Methodology:effect on opportunity • Examples • Poverty vs Income • Vacancy rate vs Home ownership rate
Methodology:Calculating Z Scores • Z Score – a statistical measure that quantifies the distance (measured in standard deviations) between data points and the mean Z Score = (Data point – Mean)/ Standard Deviation • Allows data for a geography (e.g. census tract) to be measured based on their relative distance from the average for the entire region • Raw z score performance • Mean value is always “zero” – z score indicates distance from the mean • Positive z score is always above the region’s mean, Negative z score is always below the region’s mean • Indicators with negative effect on opportunity should have all the z scores adjusted to reflect this phenomena
Methodology:Calculating Opportunity using Z Scores • Final “opportunity index” for each census tract is the average of z scores (including adjusted scores for direction) for all indicators by category • Census tracts can be ranked • Opportunity level is determined by sorting a region’s census tract z scores into ordered categories (very low, low, moderate, high, very high) • Statistical measure • Grounded in Social Science research • Most intuitive but other measures can be used • Example • Top 20% can be categorized as very high, bottom 20% - very low
Methodology:Averaging Z scores • Z score averages assume equal participation of all variables toward “Opportunity Index” calculations • No basis to provide unequal weights • Issue of weighting should be considered carefully • Need to have a strong rationale for weighting • Theoretical support would be helpful • Arbitrary weighting could skew the results
Ongoing opportunity mapping projects • Atlanta MSA, GA • State of Massachusetts • State of Connecticut
Data sources • Census Data • Non-Census Data
Census 2000 overview • Information about 115.9 million housing units and 281.4 million people across the United States • Census 2000 geography, maps and data products are available • Website: www.census.gov
Census 2000Short Form and Long Form Short form Long form
Short form • 100-percent characteristics: A limited number of questions were asked of every person and housing unit in the United States. Information is available on: • Name • Hispanic or Latino origin • Household relationship • Race • Gender • Tenure (whether the home is owned or rented) • Age
long form For the U.S. as a whole, about one in six households received the long-form questionnaire.
long form (contd.) • Additional questions were asked of a sample of persons and housing units. Data are provided on: • Population
long form (contd.) • Housing
Census 2010 • For Census 2010 • No long form questionnaire • Short form questionnaire only • To all residents in the U.S. • Ask the same set of questions • American Community Survey (ACS) to collect more detailed information • Will provide data every year rather than every 10 years • Sent to a small percentage of population on a rotating basis • No household will receive the survey more often than once every five years • It might take at least five years, and some data aggregation, to get Census tract or smaller geography level data
Available short form data • 100% data or short-form information • Summary File 1 • Counts for detailed race, Hispanic or Latino groups, and American Indian/Alaska Native tribes • Tables repeat for major race groups alone, two or more races, Hispanic or Latino, White not Hispanic or Latino • Geography: block, census tract • Summary File 2 • 36 Population tables at census tract (PCT) level • 11 Housing tables (HCT) at census tract (HCT)
Available long form data • Sample data or long-form information • Summary File 3 • 813 tables of data • Counts and cross tabulations of sample items (income, occupation, education, rent and value, vehicles available) • Lowest level of geography: block group • Summary File 4 • Tables repeated by race, Hispanic/ Latino, and American Indian and Alaska Native categories, and ancestry – 336 categories in all.
Census basedmaps • Fairly simple in calculations • Easy to display • Easy readability for the audience
Census data issues • Historical data hard to get • Inconsistent categories • Block group and census tract boundaries are regularly updated • Private data providers such as GeoLytics provide historical census data normalized to 2000 geographies • Inconsistency in data categories are minimized but still exist
Non-census data • Data not available at census is gathered from other sources • Good news!! – It is available • Bad news!! – It might not be available at the geography of analysis (census tracts) • Data needs to be manipulated to represent census tracts
Non-census dataExampleS • School data • Student poverty, test scores and teacher experience data might be available at school/District/County/State level • Transit data • Transit route data might be available with the local Metropolitan Planning Organization (MPO) • Bus-stops or train stations might be available as a point theme • Environmental data • Toxic sites and toxic release data available at EPA as point data • Parks and open spaces are available as shapefiles • Public health • Hospital locations might be available • Main issue – How to represent this data at census tract level
Spatial techniques • Mapping software offers many techniques for data manipulation. Some of these methods used in our analysis are: • Interpolation • Areal Interpolation • Buffering
Interpolation • Technique to predict value at unknown locations based on values at known locations • Example – Weather data • Areal interpolation - Transferring data from one geography to another based on the proportion of area overlapping the target area • Data aggregation • Example - Transferring jobs data at zip code level to census tracts
buffering • Buffering • Creating a buffer of a specified radius around our data point • Buffer distance decision should be research or knowledge based • Captures proximity of events such as grocery stores, jobs etc.
Data issues and considerations • Missing data • Input data average • Z score as zero • Macro level data • Jurisdictions or school districts • When do we use ratio • Grocery stores • Jobs
Future possibilities • Web-based mapping • Currently used mainly to display information • Provides tools to zoom to scale, identify and some analysis • Can be developed to exchange live information • Google mash-up • http://housingmaps.com • http://wayfaring.com • http://walkscore.com • Mapping blogs • Could residents go on-line and show where impediments to opportunity are in their neighborhood, or share their experiences? • Semantic mapping • Intelligence based Internet mapping