Data-driven part-of-speech tagging of Kiswahili

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A corpus-based survey of four electronic Swahili-English Bilingual dictionaries

In this article we survey four different electronic bilingual dictionaries for the language pair Swahili-English. Aided by a data-driven morphological analyzer and part-of-speech tagger, we quantify the coverage of the dictionaries on large monolingual corpora of Swahili. In a second series of experiments, we investigate how applicable the dictionaries are as a tool in the development of a machine translation system, by evaluating bilingual coverage on the parallel SAWA corpus. At the same time we attempt to consolidate the dictionaries into a unified lexicographic database and compare the coverage to that of its composite parts

An analysis of the trade regime in Kenya

Certain developments in international trade have made it inevitable for LDCs to commence import-substituting industrialization. The measures used to intervene in trade for this purpose have resulted in certain factor and commodity price distortions in the domestic economies of LDCs, giving rise to resource allocational and income distribution effects which are not often appreciated. Tariffs quantitative restrictions, import duty drawbacks on inputs as well as administrative controls are shown to have been widely used in Kenya to promote industrialization and exports. Different combinations of these policies have different effects on income distributions resource allocation and profits. The effects are further complicated by imperfections in import-substituting industries. Certain measures are proposed for more efficient combinations of the policies in the face of imperfections

Semi-Markov credit risk modeling for a portfolio of consumer loans in the Kenyan banking industry

Paper presented at the 11th African Finance Journal Conference, Durban, South Africa.Based on simulations of implied values for credit worthiness over a period of 5 years for 1000 consumers, we establish a case for the semi-markov models as a proxy for internal credit risk models for a portfolio of consumer loans. With ample calibration, we prove the robustness of the semi-markov models in forecasting probabilities of default and loss given default. With a view of credit risk as a reliability problem, we generate credit risk indicators as qualifications of adequacy of a loan portfolio. This informs prospective holding of capital based on forecast delinquencies as opposed to the current retrospective practice that relies on the trigger event of default. We use Monte-Carlo simulation techniques to generate consumer ratings and adopt this to the Merton model to derive the initial probability transition matrix. Initial consumer rating is in accordance with industry practice using a credit score sheet backed by the logit model. The banking credit function could espouse the study results to fulfill regulatory credit risk capital requirements for consumer loans in line with the Central Bank of Kenya Prudential Risk Guidelines or banks in other jurisdictions compliant with the Basel banking framework.Based on simulations of implied values for credit worthiness over a period of 5 years for 1000 consumers, we establish a case for the semi-markov models as a proxy for internal credit risk models for a portfolio of consumer loans. With ample calibration, we prove the robustness of the semi-markov models in forecasting probabilities of default and loss given default. With a view of credit risk as a reliability problem, we generate credit risk indicators as qualifications of adequacy of a loan portfolio. This informs prospective holding of capital based on forecast delinquencies as opposed to the current retrospective practice that relies on the trigger event of default. We use Monte-Carlo simulation techniques to generate consumer ratings and adopt this to the Merton model to derive the initial probability transition matrix. Initial consumer rating is in accordance with industry practice using a credit score sheet backed by the logit model. The banking credit function could espouse the study results to fulfill regulatory credit risk capital requirements for consumer loans in line with the Central Bank of Kenya Prudential Risk Guidelines or banks in other jurisdictions compliant with the Basel banking framework

Effect of cropping systems on accumulation of Fusarium head blight of wheat Inocula in crop residues and soils

Article PurchasedFusarium head blight (FHB) is an economically important disease of wheat, which causes reduction in grain yield both quantitatively through reduced seed weight and qualitatively by contaminating grains with mycotoxins. The effect of cropping systems on accumulation of FHB inocula in crop residues and soil was assessed at hard dough stage of wheat during the 2013 cropping season in three agro-ecological zones in Narok County, Kenya. A semi structured questionnaire was used to obtain information on wheat production practices. Fusarium spp. were isolated from crop residues and top soil, while incidence and severity of FHB were assessed at mid-anthesis. Majority of the wheat farmers were small scale producers who rotated wheat with maize, grew the two crops in adjacent fields, grew wheat in consecutive years, left wheat residues as standing hay for livestock and practiced simple land preparation methods. Prevalence of FHB was 100%, while mean incidence and severity were 20.7 and 28.4%, respectively. The most frequently isolated Fusarium spp. were F. chlamydosporum and F. graminearum in crop residues and F. oxysporum and F. proliferatum in soil. The incidence of Fusarium spp. in soil and crop residues was highly correlated to FHB incidence but not to severity of the disease. Wheat production practices affect the survival of Fusarium spp. in soil and crop residues between cropping seasons. It is therefore, recommended that after harvesting, wheat straw and maize stover should be removed from the field or be incorporated into the soil through tillage to allow faster decomposition. Inclusion of maize as a rotation crop in wheat production should also be avoided

Control of Bean Rust using Antibiotics Produced by Bacillus and Streptomyces species - Translocation and Persistence in Snap Beans

Antibiotic culture filtrates produced by Bacillus (CA5) and  Streptomyces spp. were tested for translocation and persistence when applied on snap beans inoculated with rust (Uromyces appendiculatus) in greenhouse pot experiments. The antibiotics were applied on the first trifoliate leaves and translocation was assessed as the number of rust pustules on non-treated leaflets or trifoliates while persistence was assessed as the number of rust pustules on rust infected plants at different times after antibiotic treatment. The treatments were replicated three times, each replicate consisting of a pot containing three plants. Antibiotics from both Bacillus and Streptomyceswere found to have up to 100% trans-lamina and leaflet-to-leaflet translocation but no significant trifoliate-totrifoliatetranslocation. The antibiotic culture filtrates also retained significant rust control for up to 10 days after application on the bean plant. However, no significant rust control was found on the plants after 16 days of treatment. The study indicated that the antibiotics produced by antagonistic Bacillus and Streptomyces species possess systemicactivity that can persist within the plant for over one week. These metabolites are potential bean rust control products that could be incorporated in integrated disease management program

Resistance of Kenyan wheat germplasm to Fusarium head blight and deoxynivalenol contamination

Article PurchasedFusarium head blight (FHB) of wheat causes quantitative and qualitative reduction in yield. Cultivar resistance is the most effective method of managing the disease. This study evaluated the resistance of wheat germplasm currently available in Kenya to Fusarium head blight and deoxynivalenol (DON) contamination. Nine wheat varieties and four CIMMYT lines were evaluated for susceptibility to FHB under two diverse agro-ecologies in Nakuru and Narok Counties, Kenya during the 2013 cropping season and in the greenhouse. The varieties and lines were inoculated at mid-anthesis with mixed inocula of three isolates of F. graminearum. Incidence and severity of FHB were assessed weekly and data on severity used to calculate the area under disease progress curve (AUDPC). After harvest, incidence of F. graminearum in the grain was determined and DON contamination determined by direct competitive enzyme-linked immunosorbent assay (ELISA). Incidence and severity of FHB differed significantly (p ≤ 0.05) among the varieties and lines with variety Kwale showing the least disease while line 10155 had the highest FHB levels. The AUDPC ranged from 69.8 to 120.1 for the least and most susceptible varieties, respectively. All the wheat lines and varieties accumulated DON ranging from 442 to 748 ng/g (Mean = 572 ng/g). There was a positive correlation between FHB severity, AUDPC, re-isolation frequency of F. graminearum and DON accumulation. The assessed wheat varieties and lines could be grouped into two categories: moderately tolerant and susceptible. Wheat varieties and lines available in Kenya are susceptible to FHB and DON contamination implying need for considering other strategies for managing FHB

Genetic Algorithm Based Model in Text Steganography

Steganography is an ancient art. It is used for security in open systems. It focuses on hiding secret messages inside a cover medium. The most important property of a cover medium is the amount of data that can be stored inside it without changing its noticeable properties. There are many sophisticated techniques with which to hide, analyze, and recover that hidden information. This paper discusses an exploration in the use of Genetic Algorithm operators on the cover medium. We worked with text as the cover medium with the aim of increasing robustness and capacity of hidden data. Elitism is used for the fitness function. The model presented here is applied on text files, though the idea can also be used on other file types. Our results show this approach satisfied both security and hiding capacity requirements. Furthermore, we found that an increase in the size of the secret message resulted in an exponential increase in the size of the generated cover text. We also found a close relationship between the size of the chromosome used and the population size