A Garch Approach to Measuring Efficiency: A Case Study of Nairobi Securities Exchange

The efficiency of capital markets is important if savers funds are to be channeled to the highest valued stocks. A recent review of markets in Africa categorized the Nairobi Securities Exchange as one which has no tendency towards weak form efficiency. Recent efforts to establish its efficiency have used mainly Ordinary Least Squares regression and have yielded inconclusive results. Ordinary Least Squares method assumes that the variance of the error term obtained is constant over time. However due to economic cycles some time periods are known to be generally riskier than others and the latter assumption fails to hold. There is therefore need to use other models which relax this assumption. The Autoregressive Conditionally Heteroscedastic models have been popular and widely used. They recognize that the value of the variance of errors depends upon previous lagged variances and lagged innovation terms. Kenya has also increasingly embraced ICT which may be attributed to the comparative lower cost of access to internet via computers and mobile phone technology. This is expected to increase the rational buyers in the market none of whom can influence prices in the market which may make the market more efficient. This study first used non parametric methods to check for randomness and independence of stock market returns at the Nairobi Securities Exchange. Results show that daily returns are non-random and the GARCH analysis shows that the current returns are dependent on the returns of the previous 3 days. The GARCH (3,1) model shows that returns on a particular day would be determined by the mean returns plus a white noise error term which would vary by 25.3% of return on day t-1, 9.5% of return on day t-2 and 12.05% of returns on day t-3 at 0.05 level of significance.  This signifies market inefficiency of the weak form. Keywords: Market Efficiency, Weak-Form Hypothesis, OLS, GARC

Assessing the role of law in reducing the practise of FGM/C in Kenya

Criminalization is an important aspect of anti-FGM/C policies and programs. In countries where FGM/C is practiced, the enactment of a law prohibiting the practice is an important indicator of progress toward abandonment. Criminalization is often seen as playing an important role in the declining prevalence of FGM/C. However, there is not much research on the link between the enactment of laws that prohibit and criminalize FGM/C and declining prevalence of the practice. The objectives of this study, therefore, were to assess the extent to which people obey the law on FGM/C; to investigate the reasons and causes that motivate people born into a tradition of FGM/C to obey or not to obey a law prohibiting FGM/C; and to establish the legal, policy, and program responses, across varying contexts, that would most effectively reduce the practice of FGM/C. The study was conducted in Kenya, where FGM/C is criminalized under the 2001 Children’s Act and the 2011 Prohibition of FGM Act

What do you need? 2007-08 findings from a national survey of people with diagnosed HIV

Over the past twenty-five years, both the needs of people with diagnosed HIV and our understanding of them have changed dramatically. During this time there have been many assessments of need, usually within specific geographic boundaries (such as Primary Care Trusts) but no consistent approach to describing needs has been adopted. Most needs assessments have been shaped by a variety of local factors, including the profile of existing services. This study provides an insight into the needs of people with diagnosed HIV living in the UK, based on a final sample of 1777 people. The approach taken to measuring and describing need is the same as our previous national survey (Weatherburn et al. 2002). This approach was shaped by our earlier qualitative studies exploring the experience of people with diagnosed HIV in the early days of anti-HIV treatments (Anderson et al. 2000, Anderson & Weatherburn 1999, Anderson & Weatherburn 1998). While this study uses the same methods as our 2001-2002 survey we do not draw direct comparisons with our previous data or discuss change over time. The limitations of self-completion surveys using convenience samples make change comparisons hazardous. However, it is worth noting that in any comparison with our prior data (Weatherburn et al. 2002) current levels of need very rarely seem lower than we have previously reported. The range and extent of medical and social care, support and information needs we present here reveal significant challenges for service commissioners and providers. The first challenge is to avoid drawing quick conclusions about what the patterns of need mean for service commissioning and delivery. Needs have deliberately been separated from service use because the question of what services are ‘needed’ cannot be answered simply by identifying the extent of personal needs. The overall pattern of need is a useful starting point, but this pattern is complex

Socioeconomic Factors Influencing Meat Value Addition by Rural Agribusinesses in Kenya.

Abstract: The aim of this study was to determine and quantify the socio-economic factors influencing decision by meat agribusiness operators to add value to their products, describe and characterize the existing systems of value addition in rural Kenya. The study carried out a census of 120 butchery operators in Igembe north district. Data was collected with the help of a structured questionnaire. Using a probit model to evaluate the socioeconomic factors influencing the decision to add value, the study found that credit, management's level of education and age significantly influenced the decision to engage in value addition. The study therefore recommends policy interventions to enhance access to credit, reduce illiteracy levels among rural entrepreneurs through training and extension services

Changes in socioeconomic determinants of health in a copper mine development area, northwestern Zambia

In 2011, an industrial copper mine was developed in northwestern Zambia. A health impact assessment was conducted to anticipate and address potential health impacts. To monitor these impacts, three community-based surveys were conducted in the area (2011, 2015 and 2019). We analysed these data to determine how household socioeconomic indicators - considered determinants of health - have changed in the area over time. In mine-impacted communities, between 2011 (pre-construction) and 2019, significant changes were observed for: (i) average household size (-0.6 members); (ii) proportion of mothers that have not completed primary school (+20.4%); (iii) ownership of economic assets (e.g. phones +29.3%; televisions +15.6%); (iv) access to safe drinking water (+27.4%); and (v) improved housing structures (e.g. finished roof +58.6%). When comparing changes between 2015 and 2019 in impacted communities to nearby comparison communities, there was (i) an increased proportion of mothers that had not completed primary school in comparison communities vs. no change in impacted communities; and (ii) increased ownership of economic assets in impacted vs. comparison communities in 2019. This study found generally positive changes in the socioeconomic development of impacted compared to comparison communities, with the most pronounced improvements in the early phases of mine development

Presence and distribution of mosquito larvae predators and factors influencing their abundance along the Mara River, Kenya and Tanzania

Among all the malaria controlling measures, biological control of mosquito larvae may be the cheapest and easiest to implement. This study investigated baseline predation of immature mosquitoes by macroinvertebrate predators along the Mara River, determined the diversity of predators and mosquito larvae habitats and the range of their adaptive capacity to water physico-chemical parameters. Between July and August 2011, sampling sites (n=39) along the Mara River were selected and investigated for the presence of macroinvertebrate predators and mosquito larvae. The selected sampling sites were geocoded and each dipped 20 times using standard mosquito larvae dipper to sample mosquito larvae, while a D-frame dip net was used to capture the macroinvertebrate predators. Water physico-chemical parameters (dissolved oxygen, temperature, pH, conductivity, salinity and turbidity) were taken in situ at access points, while hardness and alkalinity were measured titrimetically. The influence of macroinvertebrate predator occurrence was correlated with mosquito larvae and water quality parameters using Generalized Linear Model (GLM). Predators (n=297) belonging to 3 orders of Hemiptera (54.2%), Odonata (22.9%) and Coleoptera (22.9%), and mosquito larvae (n=4001) belonging to 10 species, which included An.gambiae s.l (44.9%), Culex spp. (34.8%) and An. coustani complex (13.8%), An. maculipalpis (3.6%), An. phaorensis (1.2%), An. funestus group (0.5%), An. azaniae (0.4%), An. hamoni (0.3%), An. christyi (0.3%), An. ardensis (0.08%), An. faini (0.07%), An. sergentii (0.05%) and 0.05% of Aedes mosquito larvae which were not identified to species level, due to lack of an appropriate key, were captured from different habitats along the Mara river. It was established that invasion of habitats by the macroinvertebrate predators were partially driven by the presence of mosquito larvae (p < 0.001), and the prevailing water physico-chemical parameters (DO, temperature, and turbidity, p <0.001). Understanding abiotic and biotic factors which favour mosquitoes and macroinveterbrate co-occurrence may contribute to the control of malaria

Conversion of natural forest results in a significant degradation of soil hydraulic properties in the highlands of Kenya

Land use change, especially conversion of native forests can have large impacts on water resources. Large scale conversion of native forests to agricultural land has occurred in the last few decades in the Mau Forest region. To quantify and understand landscape hydrologic responses, this study aimed at evaluating the effects of land use on soil infiltration, saturated hydraulic conductivity, bulk density, sorptivity, and soil moisture retention. A total of 136 plots representing five different land uses (native forest: n = 39, forest plantations: n = 14, tea plantations: n = 24, croplands: n = 23 and pasture: n = 36) were sampled in three catchments with similar parental material in the Mau Forest region, Western Kenya. Native forest topsoils (0–5 cm) had a bulk density of 1.0 ± 0.2 g cm−3 which was similar to values found for topsoils of forest plantations (1.1 ± 0.2 g cm−3), but significantly lower than topsoils from croplands (1.4 ± 0.2 g cm−3), tea plantation (1.3 ± 0.3 g cm−3) and pastures (1.4 ± 0.2 g cm−3). Similarly, soil infiltration rates were higher in native forest (76.1 ± 50 cm h−1) and in forest plantation (60.2 ± 47.9 cm h−1) than in croplands (40.5 ± 21.5 cm h‐1), tea plantations (43.3 ± 29.2 cm h−1) and pastures (13.8 ± 14.6 cm h−1). Native forest had the highest topsoil organic carbon contents (8.11 ± 2.42%) and field capacity (0.62 ±0.12 cm3 cm−3), while the highest permanent wilting point was recorded for pasture soils (mean of 0.41 ± 0.06 cm cm−3). The highest plant available water capacity was recorded for soils in native forest (mean of 0.27 ± 0.14 cm cm−3). Our study indicates that land use changes result in a significant degradation of soil hydraulic properties, which has likely resulted in changes of the regional water balance. Given the magnitude in which managed land use types have changed infiltration rates in our study area, we conclude that changes in land use types occurring in our study region in the last decades have already affected the hydrological regime of the landscapes and the compositions of flow components. The reduction in infiltration and hydraulic conductivity could result in increased surface run-off, erosion and frequency of flooding events

Recurrent mutations in the U2AF1 splicing factor in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are hematopoietic stem cell disorders that often progress to chemotherapy-resistant secondary acute myeloid leukemia (sAML). We used whole-genome sequencing to perform an unbiased comprehensive screen to discover the somatic mutations in a sample from an individual with sAML and genotyped the loci containing these mutations in the matched MDS sample. Here we show that a missense mutation affecting the serine at codon 34 (Ser34) in U2AF1 was recurrently present in 13 out of 150 (8.7%) subjects with de novo MDS, and we found suggestive evidence of an increased risk of progression to sAML associated with this mutation. U2AF1 is a U2 auxiliary factor protein that recognizes the AG splice acceptor dinucleotide at the 3' end of introns, and the alterations in U2AF1 are located in highly conserved zinc fingers of this protein. Mutant U2AF1 promotes enhanced splicing and exon skipping in reporter assays in vitro. This previously unidentified, recurrent mutation in U2AF1 implicates altered pre-mRNA splicing as a potential mechanism for MDS pathogenesis