Browsing Research Articles (Statistics & Population Studies) by Title
Now showing items 31-50 of 172
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Early pregnancy and motherhood among young women in Sub-Saharan African countries: analysis of trends and associated factors
(SAGE Publications [Commercial Publisher], 2023)This study examined the trends and factors associated with early pregnancies and motherhood among young women in three sub-Saharan African countries: Malawi, Mali, and Niger. Descriptive and multivariate analyses showed ... -
The effect of weak lensing on distance estimates from supernovae
(American Astronomical Society, 2013)Using a sample of 608 Type Ia supernovae from the SDSS-II and BOSS surveys, combined with a sample of foreground galaxies from SDSS-II, we estimate the weak lensing convergence for each supernova line of sight. We find ... -
Epidemiological analysis of spatially misaligned data: a case of highly pathogenic avian influenza virus outbreak in Nigeria
(Cambridge University Press, 2013)This research is focused on the epidemiological analysis of the transmission of the highly pathogenic avian influenza (HPAI) H5N1 virus outbreak in Nigeria. The data included 145 outbreaks together with the locations of ... -
Epidemiology, clinical characteristics and severity of gradual onset injuries in recreational road cyclists: A cross-sectional study in 21,824 cyclists - SAFER XIII
(Elsevier, 2020)Objectives: Prevalence, clinical characteristics and severity of gradual onset injuries (GOIs) in cyclists are poorly documented. We determine the prevalence, anatomical regions/sites affected and severity of GOIs among ... -
Estimation of the coherence time of stochastic oscillations from modest samples
(Oxford University Press, 2012)‘Quasi-periodic’ or ‘solar-like’ oscillations can be described by three parameters – a characteristic frequency, a coherence time (or ‘quality factor’) and the variance of the random driving process. This paper is concerned ... -
Evidence for rapid evolution of periodic variations in an ultracool dwarf
(Oxford University Press, 2006)The results of three short photometric monitoring runs on the L0 dwarf 2MASS J06050196−2342270, during three consecutive nights, are presented. The observations show the persistent presence of a 2.4-h period, with an IC ... -
Examining inequality of opportunity in the use of maternal and reproductive health interventions in Sierra Leone
(Oxford University Press, 2020)Poor countries, such as Sierra Leone, often have poor health outcomes, whereby the majority of the population cannot access lifesaving health services. Access to, and use of, maternal and reproductive health services is ... -
An exploratory look at associated factors of poverty on educational attainment in Africa and in-depth multilevel modelling for Namibia.
(BER, 2013)This study examines several indicator variables related to education and poverty in Africa from the Demographic and Health Surveys (DHS). Many have described income and education as one of the fundamental determinants ... -
An extensive search for rapid optical variability in ultracool dwarfs
(Oxford University Press, 2013)In this paper, a summary of optical time-series photometry of 125 ultracool dwarfs is given. The observing strategy was to monitor each object continuously for 2–3 h in order to ascertain whether itwas rapidly variable. ... -
Factors affecting the enrolment rate of students in Higher Education Institutions in the Gauteng province, South Africa
(SAGE, 2018)The purpose of this research is to investigate and analyse higher education institutions' enrolment and drop-out rates within the Gauteng province, South Africa. Large-scale secondary data from the General Household ... -
Factors associated with antiretroviral treatment failure among people living with HIV on antiretroviral therapy in resource- poor settings: a systematic review and metaanalysis
(BMC, 2020)Background: Despite the increase in the number of people accessing antiretroviral therapy (ART), there is limited data regarding treatment failure and its related factors among HIV-positive individuals enrolled in HIV care ... -
Factors associated with mothers’ health care‑seeking behaviours for childhood fever in Burkina Faso: Findings from repeated cross‑sectional household surveys
(BMC, 2022)Fever is one of the most frequent reasons for paediatric consultations in Burkina Faso, but health careseeking behaviours and the factors associated with health care-seeking in the event of childhood fever are poorly documented. ... -
Factors associated with patellofemoral pain in recreational road cyclists: A cross-sectional study in 59953 cyclists – SAFER XXXIII
(Elsevier, 2023)Patellofemoral pain (PFP) is a common cycling-related injury, and independent factors need to be identified to enable effective injury prevention strategies. We aim to determine factors associated with PFP in cyclists ... -
Fitting power-law distributions to data with measurement errors
(Oxford University Press, 2009)If X, which follows a power-law distribution, is observed subject to Gaussian measurement error e, thenX+e is distributed as the convolution of the power-lawand Gaussian distributions. Maximum-likelihood estimation of ... -
Fitting sinusoids to observations of rotating spotted stars
(Oxford University Press, 2007)It is assumed that K blocks (e.g. seasons) of observations are available, and the parameters characterizing a fixed-frequency sinusoidal variability (mean light level, amplitude, phase) are constant within each of the ... -
The “four sigma” limit for significant periodicities
(Springer Verlag, 2010)Most of the pulsations which have been observed in sdB stars have very low amplitudes. Detection of modes from photometric observations is usually performed by noting the most prominent peaks in a periodogram or, ... -
Further observations of Hipparcos red stars and standards for UBV(RI)C photometry
(Oxford University Press, 2007)We present homogeneous and standardized UBV(RI)C JHK photometry for over 100 M stars selected from an earlier paper on the basis of apparent photometric constancy. L photometry has been obtained for stars brighter than ... -
Gaia21bty: An exor light curve exhibiting a fuor spectrum
(Oxford University Press, 2023)Gaia21bty, a pre-main-sequence star that previously had shown aperiodic dips in its light curve, underwent a considerable ∆G ≈ 2.9 mag brightening that occurred over a few months between 2020 October and 2021 February. The ... -
Global warming and psychotraumatology of natural disasters: the case of the deadly rains and floods of April 2022 in South Africa
(Annales Médico-psychologiques, revue psychiatrique, 2023)Climate change and global warming have led to an increased incidence of flooding across the world. Against the backdrop of the recent devastating floods in the Kwazulu-Natal province of South Africa, this paper explores ... -
HE 0230–4323: An unusual pulsating hot subdwarf star
(Oxford University Press, 2007)HE 0230−4323 is a known binary, consisting of a subdwarf star and a companion which is not observable in the optical. Photometric measurements reported in this paper have shown it to be both a reflection-effect and a ...