190 research outputs found
The estimation and interpretation of adult mortality rates of African South Africans using Census 2001 data
No full textIncludes bibliographical references (leaves 74-79).This research develops estimates of mortality rates for adult Africans in South Africa for the twelve months preceding the census night, 9/10 October 2Q(B, using Census 2001 10% sample data. The approach used to estimate these rates follow the work done by Dorrington, Moultrie and Timaeus (2004) working with the full dataset, which is not publicly anilable, and demonstrate that the 10% sample can be used to produce similar results to the full database. The approach makes use of indirect estimation techniques for estimating the completeness of reporting of deaths in the vital registration system at a national level, namely the combination of Generalized Growth Balance method (GGB) and the Synthetic Extinct Generations (SEG) method adapted to allow for net immigration over the inter-censal period
Old age mortality in South Africa
No full textIncludes bibliographical references (leaves 71-74).This study estimates the mortality of the South African oldest old age population (in five year age groups from age 75 up to the open age interval 100 and above) and in the process re-estimates the numbers of people in the population at these ages at the time of the 1996 and 2001 censuses, and the 2007 Community Survey. In countries where the data on the old age population have been verified, it has been observed that the data are marred by errors in the form of age exaggeration, age digit preference, relative under/over count of the population and under-registration of deaths. These errors have been observed to have the net effect of underestimating mortality of the oldest old age groups. The current research applies the method of extinct generations to estimate indirectly the population numbers at the oldest old age groups (75 up to 100 and above) using data on reported deaths alone. Age heaping and year of birth preference in the reported deaths are assessed using ratios of the probability of death estimated from the data. Age exaggeration in the data on reported deaths is assessed using ratios of deaths compared with same ratios from a standard population. Age heaping and year of birth preference in the census/survey population is assessed using the modified Whipple's Index of age accuracy. The Generalized Growth Balance (GGB) and Synthetic Extinct Generations (SEG+delta) methods are applied to adjust for under reporting of deaths and to assess patterns of age exaggeration in the census/survey population. The difference between the estimates of the completeness of reporting of deaths from the two methods is small (less than 1 per cent) and has been observed to have little impact on the mortality estimates. Final estimates of the completeness of reporting of deaths used are those derived using the SEG+delta method. After re-estimating the population numbers and adjusting for completeness of reporting of deaths, mortality rates were then estimated. Results obtained from the method of extinct generations suggest that there is no systematic difference between the census/ survey population and the population numbers estimated from deaths except at ages 95 and above. Measures of age accuracy show that there are patterns of preferring 1910, 1914, 1918, 1920 and 1930 as the years of birth in the census/survey population and these patterns are also found in the registered deaths. The impact of these errors was investigated and the results show that preference of certain years of birth cause fluctuations in the mortality rates. Patterns observed after applying the SEG+delta method suggest that the completeness of reporting of deaths falls with age at the advanced ages (from age 90 and above) and as a result, the estimated mortality rates above this age are lower than those estimated from the United Nations Population Division (UNPD) and US Census Bureau (USCB) population projections, and Dorrington, Moultrie and Timaeus (2004). Conclusions reached are that the mortality rates for the age groups 75 to 89 derived after re-estimating the population numbers and after allowing for the fall in the completeness of reporting of deaths are lower but not significantly different from those inferred from the UNPD and USCB population projections, and estimates derived by Dorrington, Moultrie and Timaeus (2004). The research recommends mortality estimates from the UNPD since they are the closest to the estimates derived using the published census population numbers for the whole period between the nights of 9-10 October 1996 and 9-10 October 2001. However, the research produced better estimates of the oldest old age population numbers relative to the census/survey numbers
Sources of error and bias in methods of fertility estimation contingent on the P/F ratio in a time of declining fertility and rising mortality
No full textAlmost all commonly used indirect fertility estimation methods rely on the P/F ratio. As originally conceived, the ratio compares cumulated cohort fertility with cumulated period fertility on the basis of three, fairly strong, assumptions. The intention of this paper is to interrogate what happens to the results produced by the P/F ratio method as each of these three assumptions is violated, first independently, and then concurrently. These investigations are important given the generally poor quality of census data collected in developing countries, particularly sub-Saharan Africa, and the radically altering demographic conditions associated with a generalised HIV/AIDS epidemic in the region.AIDS/HIV, developing countries, estimation, fertility, indirect techniques
Old age mortality in South Africa, 1985-2011
No full textEstimating the level and trend in population mortality rates at advanced ages in South Africa is complicated by problems with both the population and death data. Population and death data, particularly in developing countries, often suffer from age misreporting - age exaggeration and digit preference. Also, censuses may under- or overestimate the population and registration of deaths is usually incomplete in developing countries (Dorrington, Moultrie and Timæus 2004). To avoid these problems, the research in this dissertation relies on the method of extinct generations and its extensions (Thatcher, Kannisto and Andreev 2002) to re-estimate the population using only the death data, which is often recorded more accurately than the population data. Since deaths are not reported completely in South Africa, the death data must be corrected before use. Death Distribution Methods (Moultrie, Dorrington, Hill et al. 2013) are used to correct the death data for incomplete registration of deaths. After correction, Near Extinct Generation methods (NEG) are used to re-estimate the population by projecting future deaths of nearly extinct cohorts. After showing that mortality rates produced using the original NEG methods are biased because of age and year of birth heaping present in the South African death data, the NEG methods are adapted to the South African context. The adapted NEG model smooths the age and year of birth heaping in the death data and produces mortality rates that are less biased than the original NEG methods. This model - referred to as the NEG-GAM model in this research - is used to re-estimate the population at each age from 70 and above and to calculate mortality rates since 1985. The population estimates aged 70+ produced using the NEG-GAM model match those from the 2011 census well. It is found that both the population and death data suffer from the same pattern of heaping, that the population and death data are affected by age exaggeration and that the death data are less affected by age exaggeration than the population data. The level and trend in mortality rates calculated using the NEG-GAM model are discussed and compared to the mortality rates in the Human Mortality Database and other studies of South African mortality. The mortality rates produced for the African and Coloured population groups appear too low at the older ages due to age exaggeration in the death data, while those for the Indian and White population groups appear to be reasonable over the entire age range. Mortality appears to be improving in the age range 70-79 for the Coloured, Indian and White population groups and deteriorating slowly for the African population group
Horace Dorrington, criminal detective: investigating the re-emergence of the rogue in Arthur Morrison\u27s The Dorrington Deed-Box (1897).
No full textRegarding The Dorrington Deed-Box (1897), Arthur Morrison?s critically neglected
second contribution to the post?Sherlock Holmes detective short story genre, the author argues
that as Dorrington is both a detective and a criminal, and the victim is the narrator, the stories
subvert the usual reassuring moral and formal conventions of the late?Victorian detective genre
Flaws, approximations and uncertainties in the estimation of the exposed-to-risk
No full textBibliography: leaves 62-64.This research analyses the theoretical basis of exposed-to-risk estimation. It defends the conventional actuarial approach against criticisms raised by Hoem (1984), and, in so doing, examines in detail the development of the actuarial profession's estimation techniques. Maximum likelihood estimates are shown to be closely related to the estimates of decremental probabilities derived using the conventional actuarial approach. The correct treatment of deaths when estimating the initial exposed-to-risk is considered and contrasted with what is often used in practice. The relationship between the initial and central exposed-to-risk is considered for a single decrement, two decrements and for select rates. The implications of alternative assumptions and approximations are considered. Some inaccuracies in tuition material of the Faculty and Institute of Actuaries and articles written about exposed-to-risk are highlighted. Other problem areas, such as the bias of calculated rates and estimation under policy and calendar year rate intervals, are also considered
Estimating adult mortality in South Africa using orphanhood and year of death data from the 2008 National Income Dynamics Study
No full textThe overall objective of this research is to investigate whether using year of death data to produce estimates of time location is a better approach than the method developed by Brass and Bamgboye (1981) and whether estimates of mortality produced using year of death data are any better than those derived using the conventional orphanhood method
Sensitivity analysis with simulated data errors : synthetic extinct generations method
No full textIncludes abstract.Includes bibliographical references (leaves 59-61).This study develops the key components of the Synthetic Extinct Generations (SEG+delta) method in trying to answer research questions raised by Dorrington and Timeaus (2008) and in the process investigates the different sets of combinations of the key components of the SEG+delta method when applied to the 23 error scenarios used by Hill and Choi (2004). In addition, the study determines the pattern of estimates of 4sfi15 per set of combinations, the combination that results in the best estimate of 45q15 per scenario and per combination of scenarios and the best combination that result in best estimate of 4sfi15 across all 23 error scenarios. The current study assesses the errors in age reported in censuses by comparing the weighted average of the ages of seven countries in the sub-Saharan African region to the age error pattern used by Hill and Choi (2004). These findings suggest that there is no significant difference (except of the zig-zag pattern in age errors at older ages in the Hill and Choi scenario) in general pattern of age errors of the sub-Saharan African region and the pattern used by Hill and Choi (2004)
Full life tables for South Africa from vital registration data, 2006-2008
No full textThis research derives a set of full life tables for South Africa as a whole and by population group using vital registration data for the period 2006-2008. Given that not all deaths are registered, the research assesses the level of completeness of death registration for the national population and for all the population groups separately by using the deaths distribution methods
Maternal mortality in high HIV prevalence countries: a critical analysis of the MMEIG methodology for estimating maternal mortality
No full textIncludes abstract.Includes bibliographical references.The main objective of this research is to analyse critically the methodology used by the Maternal Mortality Estimation Inter-Agency Group (MMEIG) to estimate maternal mortality in countries with high HIV/AIDS prevalence. This study interrogates each of the assumptions (implicit and explicit) in the MMEIG method by reviewing literature/studies that investigated each assumption
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