Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements

Land area is a fundamental component of agricultural statistics, and of analyses undertaken by agricultural economists. While household surveys in developing countries have traditionally relied on farmers' own, potentially error-prone, land ar...

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Main Authors: Kilic, Talip, Zezza, Alberto, Carletto, Calogero, Savastano, Sara
Format: Policy Research Working Paper
Language:English
en_US
Published: World Bank, Washington, DC 2013
Subjects:
GPS
WEB
Online Access:http://documents.worldbank.org/curated/en/2013/06/17875976/missingness-action-selectivity-bias-gps-based-land-area-measurements
http://hdl.handle.net/10986/15849
id okr-10986-15849
recordtype oai_dc
spelling okr-10986-158492021-04-23T14:03:23Z Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements Kilic, Talip Zezza, Alberto Carletto, Calogero Savastano, Sara AGRICULTURAL OUTPUT AGRICULTURE COMMODITY COMPUTATION CONFIDENCE INTERVALS COVARIANCE COVARIANCE MATRIX DATA ANALYSES DATA ANALYSIS DATA COLLECTION DATA ENTRY DESCRIPTIVE STATISTICS DEVELOPMENT ECONOMICS DEVELOPMENT POLICY DEVELOPMENT RESEARCH DEVELOPMENT STRATEGIES DOMAIN DOMAINS ECONOMIC DEVELOPMENT ECONOMIC INEQUALITY ENUMERATION EQUIPMENT EXPERIMENTS EXPLORATION FIELD WORK FINANCIAL RESOURCES FINANCIAL SUPPORT GLOBAL POSITIONING SYSTEM GPS GROSS VALUE HUMAN RESOURCES HYPOTHESIS TESTING IMPLEMENTING AGENCIES IMPUTATION METHOD IMPUTATION METHODS IMPUTATION PROCESS IMPUTATIONS INCOME INDEPENDENT VARIABLES INNOVATION LINEAR PREDICTION LINEAR REGRESSION LIVING STANDARDS MEASUREMENT ERRORS MISSING DATA MISSING OBSERVATIONS MISSING VALUE MISSING VALUES MULTIPLE IMPUTATION OPEN ACCESS OPPORTUNITY COSTS POLITICAL ECONOMY PRECISION PREDICTIONS PROBABILITY PRODUCTION FUNCTION PRODUCTIVITY PROPERTY RIGHTS PROTOCOL PROTOCOLS QUALITY CONTROL QUESTIONNAIRES RESEARCH METHODS RESEARCH REPORT RESEARCH WORKING PAPERS RESEARCHERS RESULT RESULTS SAMPLE SIZE SAMPLE SURVEYS SATELLITE SCIENCES SENSITIVITY ANALYSIS SIMULATIONS SOFTWARE PACKAGES STANDARD ERRORS STANDARD MEASUREMENT STATA STATISTICAL ANALYSES STATISTICAL INFERENCE STATISTICAL TECHNIQUES STATISTICIANS SUPERVISION SURPLUS LABOR SURVEY DATA SURVEY DESIGN SURVEYORS TECHNOLOGICAL INNOVATIONS TOTAL FACTOR PRODUCTIVITY TOTAL OUTPUT TRANSITION ECONOMY USE VALUE USERS VALIDITY VALUE OF OUTPUT VARIABILITY WEALTH WEB WEIGHTING land area measurement land productivity Land area is a fundamental component of agricultural statistics, and of analyses undertaken by agricultural economists. While household surveys in developing countries have traditionally relied on farmers' own, potentially error-prone, land area assessments, the availability of affordable and reliable Global Positioning System (GPS) units has made GPS-based area measurement a practical alternative. Nonetheless, in an attempt to reduce costs, keep interview durations within reasonable limits, and avoid the difficulty of asking respondents to accompany interviewers to distant plots, survey implementing agencies typically require interviewers to record GPS-based area measurements only for plots within a given radius of dwelling locations. It is, therefore, common for as much as a third of the sample plots not to be measured, and research has not shed light on the possible selection bias in analyses relying on partial data due to gaps in GPS-based area measures. This paper explores the patterns of missingness in GPS-based plot areas, and investigates their implications for land productivity estimates and the inverse scale-land productivity relationship. Using Multiple Imputation (MI) to predict missing GPS-based plot areas in nationally-representative survey data from Uganda and Tanzania, the paper highlights the potential of MI in reliably simulating the missing data, and confirms the existence of an inverse scale-land productivity relationship, which is strengthened by using the complete, multiply-imputed dataset. The study demonstrates the usefulness of judiciously reconstructed GPS-based areas in alleviating concerns over potential measurement error in farmer-reported areas, and with regards to systematic bias in plot selection for GPS-based area measurement. 2013-09-26T14:54:44Z 2013-09-26T14:54:44Z 2013-06 http://documents.worldbank.org/curated/en/2013/06/17875976/missingness-action-selectivity-bias-gps-based-land-area-measurements http://hdl.handle.net/10986/15849 English en_US Policy Research Working Paper;No. 6490 CC BY 3.0 IGO http://creativecommons.org/licenses/by/3.0/igo/ World Bank World Bank, Washington, DC Publications & Research :: Policy Research Working Paper Publications & Research Africa
repository_type Digital Repository
institution_category Foreign Institution
institution Digital Repositories
building World Bank Open Knowledge Repository
collection World Bank
language English
en_US
topic AGRICULTURAL OUTPUT
AGRICULTURE
COMMODITY
COMPUTATION
CONFIDENCE INTERVALS
COVARIANCE
COVARIANCE MATRIX
DATA ANALYSES
DATA ANALYSIS
DATA COLLECTION
DATA ENTRY
DESCRIPTIVE STATISTICS
DEVELOPMENT ECONOMICS
DEVELOPMENT POLICY
DEVELOPMENT RESEARCH
DEVELOPMENT STRATEGIES
DOMAIN
DOMAINS
ECONOMIC DEVELOPMENT
ECONOMIC INEQUALITY
ENUMERATION
EQUIPMENT
EXPERIMENTS
EXPLORATION
FIELD WORK
FINANCIAL RESOURCES
FINANCIAL SUPPORT
GLOBAL POSITIONING SYSTEM
GPS
GROSS VALUE
HUMAN RESOURCES
HYPOTHESIS TESTING
IMPLEMENTING AGENCIES
IMPUTATION METHOD
IMPUTATION METHODS
IMPUTATION PROCESS
IMPUTATIONS
INCOME
INDEPENDENT VARIABLES
INNOVATION
LINEAR PREDICTION
LINEAR REGRESSION
LIVING STANDARDS
MEASUREMENT ERRORS
MISSING DATA
MISSING OBSERVATIONS
MISSING VALUE
MISSING VALUES
MULTIPLE IMPUTATION
OPEN ACCESS
OPPORTUNITY COSTS
POLITICAL ECONOMY
PRECISION
PREDICTIONS
PROBABILITY
PRODUCTION FUNCTION
PRODUCTIVITY
PROPERTY RIGHTS
PROTOCOL
PROTOCOLS
QUALITY CONTROL
QUESTIONNAIRES
RESEARCH METHODS
RESEARCH REPORT
RESEARCH WORKING PAPERS
RESEARCHERS
RESULT
RESULTS
SAMPLE SIZE
SAMPLE SURVEYS
SATELLITE
SCIENCES
SENSITIVITY ANALYSIS
SIMULATIONS
SOFTWARE PACKAGES
STANDARD ERRORS
STANDARD MEASUREMENT
STATA
STATISTICAL ANALYSES
STATISTICAL INFERENCE
STATISTICAL TECHNIQUES
STATISTICIANS
SUPERVISION
SURPLUS LABOR
SURVEY DATA
SURVEY DESIGN
SURVEYORS
TECHNOLOGICAL INNOVATIONS
TOTAL FACTOR PRODUCTIVITY
TOTAL OUTPUT
TRANSITION ECONOMY
USE VALUE
USERS
VALIDITY
VALUE OF OUTPUT
VARIABILITY
WEALTH
WEB
WEIGHTING
land area measurement
land productivity
spellingShingle AGRICULTURAL OUTPUT
AGRICULTURE
COMMODITY
COMPUTATION
CONFIDENCE INTERVALS
COVARIANCE
COVARIANCE MATRIX
DATA ANALYSES
DATA ANALYSIS
DATA COLLECTION
DATA ENTRY
DESCRIPTIVE STATISTICS
DEVELOPMENT ECONOMICS
DEVELOPMENT POLICY
DEVELOPMENT RESEARCH
DEVELOPMENT STRATEGIES
DOMAIN
DOMAINS
ECONOMIC DEVELOPMENT
ECONOMIC INEQUALITY
ENUMERATION
EQUIPMENT
EXPERIMENTS
EXPLORATION
FIELD WORK
FINANCIAL RESOURCES
FINANCIAL SUPPORT
GLOBAL POSITIONING SYSTEM
GPS
GROSS VALUE
HUMAN RESOURCES
HYPOTHESIS TESTING
IMPLEMENTING AGENCIES
IMPUTATION METHOD
IMPUTATION METHODS
IMPUTATION PROCESS
IMPUTATIONS
INCOME
INDEPENDENT VARIABLES
INNOVATION
LINEAR PREDICTION
LINEAR REGRESSION
LIVING STANDARDS
MEASUREMENT ERRORS
MISSING DATA
MISSING OBSERVATIONS
MISSING VALUE
MISSING VALUES
MULTIPLE IMPUTATION
OPEN ACCESS
OPPORTUNITY COSTS
POLITICAL ECONOMY
PRECISION
PREDICTIONS
PROBABILITY
PRODUCTION FUNCTION
PRODUCTIVITY
PROPERTY RIGHTS
PROTOCOL
PROTOCOLS
QUALITY CONTROL
QUESTIONNAIRES
RESEARCH METHODS
RESEARCH REPORT
RESEARCH WORKING PAPERS
RESEARCHERS
RESULT
RESULTS
SAMPLE SIZE
SAMPLE SURVEYS
SATELLITE
SCIENCES
SENSITIVITY ANALYSIS
SIMULATIONS
SOFTWARE PACKAGES
STANDARD ERRORS
STANDARD MEASUREMENT
STATA
STATISTICAL ANALYSES
STATISTICAL INFERENCE
STATISTICAL TECHNIQUES
STATISTICIANS
SUPERVISION
SURPLUS LABOR
SURVEY DATA
SURVEY DESIGN
SURVEYORS
TECHNOLOGICAL INNOVATIONS
TOTAL FACTOR PRODUCTIVITY
TOTAL OUTPUT
TRANSITION ECONOMY
USE VALUE
USERS
VALIDITY
VALUE OF OUTPUT
VARIABILITY
WEALTH
WEB
WEIGHTING
land area measurement
land productivity
Kilic, Talip
Zezza, Alberto
Carletto, Calogero
Savastano, Sara
Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements
geographic_facet Africa
relation Policy Research Working Paper;No. 6490
description Land area is a fundamental component of agricultural statistics, and of analyses undertaken by agricultural economists. While household surveys in developing countries have traditionally relied on farmers' own, potentially error-prone, land area assessments, the availability of affordable and reliable Global Positioning System (GPS) units has made GPS-based area measurement a practical alternative. Nonetheless, in an attempt to reduce costs, keep interview durations within reasonable limits, and avoid the difficulty of asking respondents to accompany interviewers to distant plots, survey implementing agencies typically require interviewers to record GPS-based area measurements only for plots within a given radius of dwelling locations. It is, therefore, common for as much as a third of the sample plots not to be measured, and research has not shed light on the possible selection bias in analyses relying on partial data due to gaps in GPS-based area measures. This paper explores the patterns of missingness in GPS-based plot areas, and investigates their implications for land productivity estimates and the inverse scale-land productivity relationship. Using Multiple Imputation (MI) to predict missing GPS-based plot areas in nationally-representative survey data from Uganda and Tanzania, the paper highlights the potential of MI in reliably simulating the missing data, and confirms the existence of an inverse scale-land productivity relationship, which is strengthened by using the complete, multiply-imputed dataset. The study demonstrates the usefulness of judiciously reconstructed GPS-based areas in alleviating concerns over potential measurement error in farmer-reported areas, and with regards to systematic bias in plot selection for GPS-based area measurement.
format Publications & Research :: Policy Research Working Paper
author Kilic, Talip
Zezza, Alberto
Carletto, Calogero
Savastano, Sara
author_facet Kilic, Talip
Zezza, Alberto
Carletto, Calogero
Savastano, Sara
author_sort Kilic, Talip
title Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements
title_short Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements
title_full Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements
title_fullStr Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements
title_full_unstemmed Missing(ness) in Action : Selectivity Bias in GPS-Based Land Area Measurements
title_sort missing(ness) in action : selectivity bias in gps-based land area measurements
publisher World Bank, Washington, DC
publishDate 2013
url http://documents.worldbank.org/curated/en/2013/06/17875976/missingness-action-selectivity-bias-gps-based-land-area-measurements
http://hdl.handle.net/10986/15849
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