A causal model of the size distribution of family income

1982 ◽  
Vol 10 (4) ◽  
pp. 86-91
Author(s):  
Richard J. Gomez
Keyword(s):  
Size Distribution ◽  
Family Income ◽  
Causal Model

Flock size and formation in black-billed gulls

1982 ◽  
Vol 60 (8) ◽  
pp. 1806-1811 ◽  
Author(s):  
Roger M. Evans
Keyword(s):  
Size Distribution ◽  
Causal Model ◽  
Causal Explanation ◽  
Flock Size ◽  
Group Foraging ◽  
Foraging Site ◽  
Site Tenacity

Black-billed gulls (Larus bulleri) depart form breeding colonies and foraging sites in nonrandom, clumped formations (flocks). Flocks leaving colonies were significantly smaller than those leaving foraging sites, in part owing to more "upflights" at foraging sites. When more birds left a colony per unit time, flocks were both larger and more frequent.A causal model was developed based on the assumptions that flock departures from a colony or foraging site result from the effects of social attractions superimposed on otherwise random departure intervals. This model successfully predicted the size distribution of flocks departing from four colonies and foraging sites. In conjunction with the concepts of site tenacity and habituation, the model also permits a causal explanation of differences in the size of flocks departing colonies compared with foraging sites, and of size differences in flocks arising from "upflights" as opposed to the more common "straggling" columnar formations. The model and results are consistent with the hypothesis that colonies function as assembly points that facilitate group foraging.

scholarly journals A Multi-causal Model for Chronic Malnutrition and Anemia in a Population of Rural Coastal Children in Ecuador

2019 ◽  
Vol 24 (4) ◽  
pp. 472-482
Author(s):  
María F. Rivadeneira ◽  
Ana L. Moncayo ◽  
Betzabé Tello ◽  
Ana L. Torres ◽  
Gladys J. Buitrón ◽  
...  
Keyword(s):  
Prenatal Care ◽  
Family Income ◽  
Causal Model ◽  
Prevalence Ratio ◽  
Access To Health Services ◽  
Chronic Malnutrition ◽  
Access To Health ◽  
Care Practices ◽  
Independent Association ◽  
Children Under 5

Abstract Objectives Chronic malnutrition and anemia are prevalent in developing countries. This research aimed to determine the prevalence of chronic malnutrition and anemia and their associated factors in children under five using a multi-causal model in a rural community in the coast of Ecuador. Methods The study included 314 children under 5 years old who were residents of San Isidro, Ecuador. Indicators of chronic malnutrition and anemia were identified. Mothers/caregivers were surveyed on socio-economic and environmental conditions, feeding and care practices, access to health services and biological characteristics. Bivariate and multivariable Poisson regression were performed. Results The prevalence was 12.42% (n = 39) for chronic malnutrition and 16.98% (n = 54) for anemia. There was a significant and independent association between chronic malnutrition and family income less than $80 USD per month (Prevalence Ratio [PR] = 2.74, 95% CI 1.04, 7.20), maternal height less than 150 cm (PR 3.00, 95% CI 1.69, 5.32) and residence in a household with more than 4 children (PR 3.05, 95% CI 1.48, 6.29). Anemia was 2.57 times higher (95% CI 1.17, 5.65) in children with more than two episodes of diarrhea in the last 6 months. Prenatal care (5 to 8 visits) provided a protective effect for anemia (PR 0.48, 95% CI 0.27, 0.89). Conclusions for Practice Findings support the need for comprehensive interventions targeted toward chronic malnutrition and anemia in children from rural coastal communities. Improvement of socioeconomic conditions, family planning, prenatal care and reduction of diarrheal diseases should be prioritized.

Sign in / Sign up

Export Citation Format

Share Document