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Two long-established stylized facts in the urban and development economics literatures are that: (a) a country's level of economic development is strongly positively correlated with its level of urbanization; and (b) a country's level of urbanization is strongly negatively correlated with the size of its agricultural sector. However, countries in the Latin America and Caribbean region appear to depart significantly from the rest of the world in these two basic relationships. Although Latin American countries appear to be significantly more urbanized than predicted based on these global relationships, Caribbean countries appear significantly less urbanized. However, analyses involving cross-country comparisons of urbanization levels are undermined by systematic measurement errors arising from differences in how countries define their urban areas. This paper reexamines whether Latin America and Caribbean countries differ from the rest of the world in the basic stylized facts of urbanization, development, and structural transformation. The analysis makes use of two alternative methodologies for the consistent definition of urban areas across countries: the Agglomeration Index methodology and a methodology based on the identification of dense spatially contiguous clusters of population. Both methodologies rely on globally gridded population data sets as input. There exist several such data sets, and so the paper also assesses the robustness of the findings to the choice of input population layer.

Development --- Measurement Error --- Urbanization

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This paper discusses the challenges associated with collecting time-use data in developing countries. The paper suggests potential solutions, concentrating on the two most common time-use methods used in development settings: stylized questions and time diaries. The paper identifies a significant lack of rigorous empirical research comparing these methods in development settings, and begins to fill this gap by analyzing data from Women's Empowerment in Agriculture Index surveys in Bangladesh and Uganda. The surveys include stylized questions and time diary estimates for the same individual. The study finds limited evidence that stylized questions are more feasible (in terms of interview length) but also less accurate, compared with time diaries. These results are attributed to the relatively greater cognitive burden imposed on respondents by stylized questions. The paper discusses the importance of broadening the scope of time-use research to capture the quantity and quality of time, to achieve richer insights into gendered time-use patterns and trends. The paper suggests a path forward that combines mainstream time-use data collection methods with promising methodological innovations from other disciplines.

Measurement Error --- Recall Error --- Time Use

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Sweet potato (Ipomoea batatas) varieties have important nutritional differences and there is strong interest to identify nutritionally superior varieties for dissemination. In agricultural household surveys, this information is often collected based on the farmer's self-report. However, recent evidence has demonstrated the inherent difficulties in correctly identifying varieties from self-report information. This study examines the accuracy of self-report information on varietal identification from a data capture experiment on sweet potato varieties in southern Ethiopia. Three household-based methods of identifying varietal adoption are tested against the benchmark of DNA fingerprinting: (A) elicitation from farmers with basic questions for the most widely planted variety; (B) farmer elicitation on five sweet potato phenotypic attributes by showing a visual-aid protocol; and (C) enumerator recording observations on five sweet potato phenotypic attributes using a visual-aid protocol and visiting the field. The reference being the DNA fingerprinting, about 30 percent of improved varieties were identified as local or non-improved, and 20 percent of farmers identified a variety as local when it was in fact improved. The variety names given by farmers delivered inconsistent and fuzzy varietal identities. The visual-aid protocols employed in methods B and C were better than method A, but still way below the adoption estimates given by the DNA fingerprinting method. The findings suggest that estimating the adoption of improved varieties with methods based on farmer self-reports is questionable, and point toward a wider use of DNA fingerprinting, likely to become the gold standard for crop varietal identification.

Agricultural Survey --- Agriculture --- Measurement Error --- Sweet Potato --- Varietal Identification

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This study examines recall bias in farm labor by conducting a randomized survey experiment in Ghana. Hours of farm labor obtained from a recall survey conducted at the end of the season are compared with data collected weekly throughout the season. The study finds that the recall method overestimates farm labor per person per plot by about 10 percent, controlling for observable differences at baseline. Recall bias in farm labor per person per plot is accounted for by the fact that households in the recall group report fewer marginal plots and farm workers, denoted here as listing bias. This listing bias also creates a countervailing effect on hours of farm labor at higher levels of aggregation, so that the recall method underestimates farm labor per plot and per household and overestimates the labor productivity of household-operated farms. Consistent with the notion that recall bias is linked to the cognitive burden of reporting on past events, the study finds that recall bias in farm labor has a strong educational gradient.

Agricultural Productivity --- Agriculture --- Education --- Educational Sciences --- Farm Labor --- Food Security --- Gender --- Gender and Development --- Labor Markets --- Measurement Error --- Recall Bias

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Metrology is the science of measurements. It is traceable to measurement standards, thus to the concept of measurement accuracy, which is used in all natural and technical sciences, as well as in some fields of social sciences and liberal arts. The key problem is one of obtaining knowledge of the physical reality, which is observed through a prism of an assemblage of quantity properties describing the objectively-real world. One of the fundamental tasks of metrology is the development of theoretical and methodological aspects of the procedure of getting an accurate knowledge relating to objects

Measurement --- Metrology. --- Science --- Weights and measures --- Measuring --- Mensuration --- Mathematics --- Technology --- Metrology --- Physical measurements --- Standards. --- Diagnostic Estimate Methods. --- Evaluating Procedure. --- Mathematical Mean Value Determination. --- Measurement Error. --- Signal Filtration.