scholarly journals Detection of density-dependent effects on caribou numbers from a series of census data

Rangifer ◽  
1991 ◽  
Vol 11 (4) ◽  
pp. 36 ◽  
Author(s):  
Francois Messier
Keyword(s):  
Density Dependence ◽  
Census Data ◽  
Permutation Test ◽  
Sampling Error ◽  
A Priori ◽  
Randomization Test ◽  
Equilibrium Density ◽  
Population Estimates ◽  
Computer Assisted ◽  
Density Independence

The main objective of this paper is to review and discuss the applicability of statistical procedures for the detection of density dependence based on a series of annual or multi-annual censuses. Regression models for which the statistic value under the null hypothesis of density independence is set a priori (slope = 0 or 1), generate spurious indications of density dependence. These tests are inappropriate because low sample sizes, high variance, and sampling error consistently bias the slope when applied to a finite number of population estimates. Two distribution-free tests are reviewed for which the rejection region for the hypothesis of density independence is derived intrinsically from the data through a computer-assisted permutation process. The "randomization test" gives the best results as the presence of a pronounced trend in the sequence of population estimates does not affect test results. The other non-parametric test, the "permutation test", gives reliable results only if the population fluctuates around a long-term equilibrium density. Both procedures are applied to three sets of data (Pukaskwa herd, Avalon herd, and a hypothetical example) that represent quite divergent population trajectories over time.

Collection of Ego-Centered Network Data with Computer-Assisted Interviews

Methodology ◽  
2006 ◽  
Vol 2 (1) ◽  
pp. 7-15 ◽  
Author(s):  
Joachim Gerich ◽  
Roland Lehner
Keyword(s):  
Survey Methods ◽  
A Priori ◽  
Dynamic Structure ◽  
Computer Assisted ◽  
Network Data ◽  
Great Effort ◽  
Self Administration ◽  
Face To Face ◽  
Full Network

Although ego-centered network data provide information that is limited in various ways as compared with full network data, an ego-centered design can be used without the need for a priori and researcher-defined network borders. Moreover, ego-centered network data can be obtained with traditional survey methods. However, due to the dynamic structure of the questionnaires involved, a great effort is required on the part of either respondents (with self-administration) or interviewers (with face-to-face interviews). As an alternative, we will show the advantages of using CASI (computer-assisted self-administered interview) methods for the collection of ego-centered network data as applied in a study on the role of social networks in substance use among college students.

scholarly journals How Does Administrative Data Compare with Census Data for the Measurement of Internal Migration? The Case of Northern Ireland, 2001–2011

2021 ◽  
Author(s):  
Brian Foley ◽  
Tony Champion ◽  
Ian Shuttleworth
Keyword(s):  
Administrative Data ◽  
Internal Migration ◽  
Census Data ◽  
Local Population ◽  
Population Data ◽  
Population Estimates ◽  
Demographic Groups ◽  
Small Areas ◽  
Intercensal Period ◽  
Statistical Agencies

AbstractThe paper compares and contrasts internal migration measured by healthcard-based administrative data with census figures. This is useful because the collection of population data, its processing, and its dissemination by statistical agencies is becoming more reliant on administrative data. Statistical agencies already use healthcard data to make migration estimates and are increasingly confident about local population estimates from administrative sources. This analysis goes further than this work as it assesses how far healthcard data can produce reliable data products of the kind to which academics are accustomed. It does this by examining migration events versus transitions over a full intercensal period; population flows into and out of small areas; and the extent to which it produces microdata on migration equivalent to that in the census. It is shown that for most demographic groups and places healthcard data is an adequate substitute for census-based migration counts, the exceptions being for student households and younger people. However, census-like information is still needed to provide covariates for analysis and this will still be required whatever the future of the traditional census.

scholarly journals Early Medieval Central Asian Population Estimates

2017 ◽  
Vol 60 (6) ◽  
pp. 788-817
Author(s):  
Étienne de la Vaissière
Keyword(s):  
Central Asia ◽  
Agricultural Land ◽  
Census Data ◽  
Asian Population ◽  
Population Estimates ◽  
Early Medieval ◽  
The North ◽  
Central Asian ◽  
The Individual

Abstract Census data from 8th-century Eastern Central Asian oases, combined with the measurements of the oases and data from archives discovered there, allow us to calculate estimates both of the individual oases’ populations and of their respective feeding capacities, which is to say the number of people who could be fed from the output of one hectare of agricultural land. These numbers in turn have parallels in Western Central Asia, where oasis sizes can also be calculated by examination of preserved archaeological landscapes and oasis walls. It is therefore possible to reach a rough idea of the populations dwelling in the main oases and valleys of sedentary Central Asia. As regards nomadic regions, the data are far more hypothetical, but references in certain sources to the sizes of nomad armies and rates of nomadic military levying can allow us to calculate at least the possible scales of magnitude for populations living to the north of the Tianshan.

Demogaphic: The Jewish population of Leeds – how many Jews?

2019 ◽  
pp. 35-46
Author(s):  
Nigel Grizzard
Keyword(s):  
Jewish Population ◽  
Census Data ◽  
Religious Affiliation ◽  
Demographic Data ◽  
Population Estimates ◽  
Place Of Birth ◽  
Death Rates

The chapter attempts the difficult task of estimating the changing Jewish population of Leeds, without reliable census data. Before the present century, the census did not record religious affiliation. Surrogate demographic data has to be used based on place of birth; for the 1881, 1891 and 1901 census, if the place of birth was stated as Russia it has been used to form the basis of population estimates. The name COHEN is used as an additional indicator, as well as birth and death rates. The Jewish Year Book estimates are listed.

scholarly journals Spatial distribution and temporal trends of leprosy in Uganda, 2012–2016: a retrospective analysis of public health surveillance data

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Freda Loy Aceng ◽  
Herman-Joseph Kawuma ◽  
Robert Majwala ◽  
Maureen Lamunu ◽  
Alex Riolexus Ario ◽  
...  
Keyword(s):  
Public Health ◽  
Surveillance System ◽  
Census Data ◽  
Temporal Trends ◽  
Northern Region ◽  
Control Measures ◽  
Population Estimates ◽  
Case Detection ◽  
Detection Rates ◽  
Leprosy Case

Abstract Background Leprosy is a neglected disease that poses a significant challenge to public health in Uganda. The disease is endemic in Uganda, with 40% of the districts in the country affected in 2016, when 42 out of 112 districts notified the National Tuberculosis and Leprosy Program (NTLP) of at least one case of leprosy. We determined the spatial and temporal trends of leprosy in Uganda during 2012–2016 to inform control measures. Methods We analyzed quarterly leprosy case-finding data, reported from districts to the Uganda National Leprosy Surveillance system (managed by NTLP) during 2012–2016. We calculated new case detection by reporting district and administrative regions of treatment during this period. New case detection was defined as new leprosy cases diagnosed by the Uganda health services divided by regional population; population estimates were based on 2014 census data. We used logistic regression analysis in Epi-Info version 7.2.0 to determine temporal trends. Population estimates were based on 2014 census data. We used QGIS software to draw choropleth maps showing leprosy case detection rates, assumed to approximate the new case detection rates, per 100,000 population. Results During 2012–2016, there was 7% annual decrease in reported leprosy cases in Uganda each year (p = 0.0001), largely driven by declines in the eastern (14%/year, p = 0.0008) and central (11%/year, p = 0.03) regions. Declines in reported cases in the western (9%/year, p = 0.12) and northern (4%/year, p = 0.16) regions were not significant. The combined new case detection rates from 2012 to 2016 for the ten most-affected districts showed that 70% were from the northern region, 20% from the eastern, 10% from the western and 10% from the central regions. Conclusion There was a decreasing trend in leprosy new case detection in Uganda during 2012–2016; however, the declining trends were not consistent in all regions. The Northern region consistently identified more leprosy cases compared to the other regions. We recommend evaluation of the leprosy surveillance system to ascertain the leprosy situation.

The estimation of density dependence using census data from several sites

Oecologia ◽  
2002 ◽  
Vol 133 (4) ◽  
pp. 466-473 ◽  
Author(s):  
S. Langton ◽  
N. Aebischer ◽  
P. Robertson
Keyword(s):  
Density Dependence ◽  
Census Data

scholarly journals Performance of a Randomization Test for Single-Subject 15O-Water PET Activation Studies

1997 ◽  
Vol 17 (10) ◽  
pp. 1033-1039 ◽  
Author(s):  
Marco Halber ◽  
Karl Herholz ◽  
Klaus Wienhard ◽  
Gunter Pawlik ◽  
Wolf-Dieter Heiss
Keyword(s):  
Permutation Test ◽  
Inferior Frontal Gyrus ◽  
Test Procedure ◽  
Temporal Cortex ◽  
Randomization Test ◽  
Single Subject ◽  
Precentral Gyrus ◽  
Positron Emission ◽  
Filter Kernel ◽  
The Difference

We adapted and implemented a permutation test ( Holmes 1994 ) to single-subject positron emission tomography (PET) activation studies with multiple replications of conditions. That test determines the experimentwise α error as well as location and extent of focal activations in each individual. Its performance was assessed in five normal volunteers, using 15O-H2O-PET data acquired on a high-resolution scanner, with septa retracted (3D mode), during functional activation by repeating words versus resting (four replications each). Calculated α errors decreased and the size of activated tissue volumes (voxels with P ≤ 0.05) increased with increasing filter kernel size applied to the difference images. At a filter kernel of 12 mm Gaussian full width at half maximum, significant focal activations were seen bilaterally in superior temporal cortex, including Brodmann's areas 41 and 42, in all five subjects. Additional foci were detected in the precentral gyrus, left inferior frontal gyrus, supplementary motor area, and cerebellum of several subjects. The average CBF increase in activated voxels ranged from 17.6% to 28.7%. Activated volumes were smaller than those detected with a standard parametric test procedure. We conclude that the permutation test is a less sensitive procedure, having the advantage of not depending on unproven distributional assumptions, that detects strong activation foci in individual subjects with high reproducibility.

Censuses of penguin, blue-eyed shag, and southern giant petrel populations in the Antarctic Peninsula region, 1994–2000

Polar Record ◽  
2000 ◽  
Vol 36 (199) ◽  
pp. 323-334 ◽  
Author(s):  
Ron Naveen ◽  
Steven C. Forrest ◽  
Rosemary G. Dagit ◽  
Louise K. Blight ◽  
Wayne Z. Trivelpiece ◽  
...  
Keyword(s):  
Antarctic Peninsula ◽  
Census Data ◽  
Population Data ◽  
Gentoo Penguin ◽  
Population Estimates ◽  
Giant Petrel ◽  
Southern Giant Petrel ◽  
The Antarctic ◽  
First Time ◽  
Pygoscelid Penguins

AbstractThis paper presents new census data and population estimates for penguins, blue-eyed shags, and southern giant petrels from 26 sites in the Antarctic Peninsula, collected by the Antarctic Site Inventory from 1994 to 2000. For nine sites, population data or estimates are published for the first time. The newly discovered gentoo penguin population of 215 nests at Herofna Island (63°24'S, 54°36'W) represents the easternmost location where this species has been found breeding in the Peninsula. All three pygoscelid penguins — gentoo, Adelie, and chinstrap — were found breeding at Gourdin Island (63° 12'S, 57° 18'W), the fourth known site where these species nest contiguously in the Peninsula. During the period, significant declines in nesting populations of blue-eyed shag were documented at three northwestern Peninsula locations.

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