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1.
PLoS One ; 19(1): e0296667, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38215177

RESUMEN

This study tests for potential bias in self-reported innovation due to the inclusion of a research and development (R&D) module that only microbusinesses (less than 10 employees) receive in the Annual Business Survey (ABS). Previous research found that respondents to combined innovation/R&D surveys reported innovation at lower rates than respondents to innovation-only surveys. A regression discontinuity design is used to test whether microbusinesses, which constitute a significant portion of U.S. firms with employees, are less likely to report innovation compared to other small businesses. In the vicinity of the 10-employee threshold, the study does not detect statistically significant biases for new-to-market and new-to-business product innovation. Statistical power analysis confirms the nonexistence of biases with a high power. Comparing the survey design of ABS to earlier combined innovation/R&D surveys provides valuable insights for the proposed integration of multiple Federal surveys into a single enterprise platform survey. The findings also have important implications for the accuracy and reliability of innovation data used as an input to policymaking and business development strategies in the United States.


Asunto(s)
Comercio , Pequeña Empresa , Humanos , Estados Unidos , Autoinforme , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
2.
Artículo en Inglés | MEDLINE | ID: mdl-35572046

RESUMEN

The COVID-19 pandemic initially caused worldwide concerns about food insecurity. Tweets analyzed in real-time may help food assistance providers target food supplies to where they are most urgently needed. In this exploratory study, we use natural language processing to extract sentiments and emotions expressed in food security-related tweets early in the pandemic in U.S. states. The emotion joy dominated in these tweets nationally, but only anger, disgust, and fear were also statistically correlated with contemporaneous food insufficiency rates reported in the Household Pulse Survey; more nuanced and statistically stronger correlations are detected within states, including a negative correlation with joy.

3.
Soc Sci Med ; 246: 112759, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31923836

RESUMEN

Since 1980, average life expectancy in the United States has increased by roughly five years; however, in recent years it has been declining. At the same time, spatial variation in life expectancy has been growing. To explore reasons for this trend, some researchers have focused on morbidity factors, while others have focused on how mortality trends differ by personal characteristics. However, the effect community characteristics may play in expanding the spatial heterogeneity has not yet been fully explored. Using a spatial Durbin error model, we explore how community and demographic factors influence county-level life expectancy in 2014, controlling for life expectancy in 1980 and migration over time, and analyzing men and women separately. We find that community characteristics are important in determining life expectancy and that there may be a role for policy makers in addressing factors that are associated with lower life expectancy in some regions.


Asunto(s)
Esperanza de Vida , Mortalidad , Femenino , Humanos , Masculino , Morbilidad , Estados Unidos/epidemiología
4.
PLoS One ; 14(7): e0220295, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31339950

RESUMEN

Recent years have seen tremendous advances in the scientific study of networks, as more and larger data sets of relationships among nodes have become available in many different fields. This has led to pathbreaking discoveries of near-universal network behavior over time, including the principle of preferential attachment and the emergence of scaling in complex networks. Missing from the set of network analysis methods to date is a measure that describes for each node how its relationship (or links) with other nodes changes from one period to the next. Conventional measures of network change for the most part show how the degrees of a node change; these are scalar comparisons. Our contribution is to use, for the first time, the cosine similarity to capture not just the change in degrees of a node but its relationship to other nodes. These are vector (or matrix)-based comparisons, rather than scalar, and we refer to them as "rewiring" coefficients. We apply this measure to three different networks over time to show the differences in the two types of measures. In general, bigger increases in our rewiring measure are associated with larger increases in network density, but this is not always the case.


Asunto(s)
Algoritmos , Redes Comunitarias/organización & administración , Red Social , Comercio , Redes Comunitarias/economía , Redes Comunitarias/estadística & datos numéricos , Conducta Cooperativa , Países Desarrollados/economía , Países Desarrollados/estadística & datos numéricos , Recesión Económica/estadística & datos numéricos , Economía/estadística & datos numéricos , Humanos , Internacionalidad , Relaciones Interpersonales , Modelos Biológicos , Factores de Tiempo
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