Methods for Estimating Population Total, Age Distribution and Vital Rates in Family Reconstitution Studies

1978 ◽  
Vol 32 (3) ◽  
pp. 511 ◽  
Author(s):  
Allan Sharlan
Keyword(s):  
Age Distribution ◽  
Vital Rates ◽  
Population Total ◽  
Family Reconstitution

scholarly journals Reconstructing population dynamics of a threatened marine mammal using multiple data sets

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jeffrey A. Hostetler ◽  
Julien Martin ◽  
Michael Kosempa ◽  
Holly H. Edwards ◽  
Kari A. Rood ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Marine Mammal ◽  
Conservation Status ◽  
Age Distribution ◽  
Credible Interval ◽  
Parameter Estimates ◽  
Observation Data ◽  
Vital Rates ◽  
Multiple Sources ◽  
Multiple Data Sets

AbstractModels of marine mammal population dynamics have been used extensively to predict abundance. A less common application of these models is to reconstruct historical population dynamics, filling in gaps in observation data by integrating information from multiple sources. We developed an integrated population model for the Florida manatee (Trichechus manatus latirostris) to reconstruct its population dynamics in the southwest region of the state over the past 20 years. Our model improved precision of key parameter estimates and permitted inference on poorly known parameters. Population growth was slow (averaging 1.02; 95% credible interval 1.01–1.03) but not steady, and an unusual mortality event in 2013 led to an estimated net loss of 332 (217–466) manatees. Our analyses showed that precise estimates of abundance could be derived from estimates of vital rates and a few input estimates of abundance, which may mean costly surveys to estimate abundance don’t need to be conducted as frequently. Our study also shows that retrospective analyses can be useful to: (1) model the transient dynamics of age distribution; (2) assess and communicate the conservation status of wild populations; and (3) improve our understanding of environmental effects on population dynamics and thus enhance our ability to forecast.

Changing Age Distribution of Deep Venous Thrombosis In the United States

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1539-1539
Author(s):  
Prabhu Viswanathan ◽  
Lakshmanan Krishnamurti
Keyword(s):  
United States ◽  
Total Population ◽  
Conflicts Of Interest ◽  
Age Distribution ◽  
Age Groups ◽  
The United States ◽  
Population Census ◽  
Analysis Tool ◽  
Principal Diagnosis ◽  
Population Total

Abstract Abstract 1539 Background: Deep vein thrombosis (DVT) and pulmonary embolism (PE) are the major cardiovascular killers in the hospital setting. While there is increasing understanding of the public health importance of DVT there are limited data on the trends in the distribution of DVT in different age groups. Aim: The aim of this study was to study national trends in age distribution of DVT in patients over the age of 45 years in the last decade. Methods: We used the National Inpatient Sample (NIS) to analyze the epidemiology of hospitalizations in various age groups from 1997 – 2007. The NIS is a part of the Healthcare Cost and Utilization Project (HCUP) sponsored by the Agency for Health Care Research and Quality (AHRQ) and contains information from a 20% stratified sample of hospitals extrapolated to show the entire national utilization in United States. For our study we selected the following ICD-9 codes to represent DVT (ICD-9 codes 451.11, 451.19, 451.2, 451.81, 451.9, 453.40, 453.41, 453.42, 453.8, 453.9). For each hospitalization, NIS allows a total of up to 15 diagnostic entries. The entry in the diagnostic (DX) field 1 is called the Principal Diagnosis (PD) is the principal reason for admission and the entries between DX fields 1 and DX field 15 are called all-listed diagnoses and include the principal diagnosis plus additional conditions that coexist at the time of admission, or that develop during the stay. We derived at Secondary diagnoses (SD) by excluding PD of DVT from the list of AD. U.S. Population Census Bureau was used to calculate the change in population. Predictive Analytics Software, IBM PASW Statistics 18.0 data analysis tool were used for data mining and statistical analysis and least square regression analysis was used to calculate ‘p’ value. Result: From 1997 – 2007, Conclusion: These data describe for the first time, trends in the relative contribution of different age groups to the burden of DVT among hospitalized patients in the United States. The population between age group 45–64 years is growing symmetrically as a proportion of the total population, total hospitalized population and total hospitalized population with DVT. On the other hand the population 65–84 years of age is decreasing as a proportion of the total hospitalized population with DVT to an even greater degree than as a proportion of the total population and the total hospitalized population. The group over 85 years remains a disproportionately large contributor to the population with DVT. These data suggest the need for greater study of the distribution of DVT, the underlying causes and potential strategies to prevent DVT in different age groups Disclosures: No relevant conflicts of interest to declare.

scholarly journals Two centuries of demographic change in Canada

2014 ◽  
Vol 41 (1-2) ◽  
pp. 1
Author(s):  
Barry Edmonston
Keyword(s):  
Age Structure ◽  
Demographic Change ◽  
Demographic Transition ◽  
Age Distribution ◽  
Major Change ◽  
Low Fertility ◽  
High Fertility ◽  
Vital Rates ◽  
Demographic Processes ◽  
Negative Population

One key aspect of the demographic transition—the shift from high mortality and high fertility to low mortality and low fertility is a major change in the population’s age distribution from a pyramid-shaped young age structure to a pillar-shaped old age structure. This paper discusses two demographic processes affected by changes in age structure. First, there are effects on vital rates, with important differences in the observed crude rates and the implied intrinsic vital rates. Second, changes in age structure influence population momentum. More recently, demographers have noted that older age distributions associated with fertility levels below replacement have negative population momentum. Although the demographic transition has been well-described for many countries, demographers have seldom analyzed intrinsic vital rates and population momentum over time, which are dynamic processes affected by changes in the population age structure and which, in turn, influence future changes in population growth and size. This paper uses new data and methods to analyze intrinsic vital rates and population momentum across two centuries of demographic change in Canada 

Defects in Resin Transfer Molded Plaques Due to Resin Age Distribution During Mold Filling

1996 ◽  
Vol 11 (3) ◽  
pp. 284-290 ◽  
Author(s):  
N. S. Losure ◽  
K. Jayaraman ◽  
C. A. Petty
Keyword(s):  
Age Distribution ◽  
Mold Filling
Sign in / Sign up

Export Citation Format

Share Document