| 1. |
- Dushimirimana, Justine, et al.
(författare)
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Growth curve model for analyzing the effects of Calcium foliar feed on the wilting rate of post-harvest rose flowers
- 2021
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Ingår i: African Journal of Applied Statistics. - : The Statistics and Probability African Society. - 2316-0861. ; 8:2, s. 1181-1197
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Tidskriftsartikel (refereegranskat)abstract
- Cut rose flowers contribute to the economy and development of the export markets for several developing countries. Despite this contribution, profitable production of rose flowers is limited by wilting which leads to lower production. This paper aims to investigate the effects of Calcium foliar feed on the wilting rate of post-harvest rose flowers using the Growth Curve Model. This method was applied to the data consisting of wilting scores on five treatment groups. The Likelihood ratio test was used to test the growth curve and the equality of the growth curves in all groups. Results revealed that the expected growth curves for all groups followed different quadratic functions. The results also revealed that the wilting rate increased with the increase of calcium concentration compared to the control. This leads to a useful model for policy-makers or further analyses.
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| 2. |
- John Mwakisisile, Andongwisye, et al.
(författare)
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Projecting Tanzania Pension Fund System
- 2017
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Ingår i: African Journal of Applied Statistics. - : Afrika Statistika - SPAS. - 2316-0861. ; 4:1, s. 193-218
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Tidskriftsartikel (refereegranskat)abstract
- A mandatory Tanzania pension fund with a final salary defined benefit is analyzed. This fund is a contributory pay-as-you-go defined benefit pension system which is much affected by the change in demography. Two kinds of pension benefit, a commuted (at retirement) and a monthly (old age) pension are considered. A decisive factor in the analysis is the increased life expectancy of members of the fund. The projection of the fund’s future members and retirees is done using expected mortality rates of working population and expected longevity. The future contributions, benefits, asset values and liabilities are analyzed. The projection shows that the fund will not be fully sustainable on a long term due to the increase in life expectancy of its members. The contributions will not cover the benefit payouts and the asset value will not fully cover liabilities. Evaluation of some possible reforms of the fund shows that they cannot guarantee a long-term sustainability. Higher returns on asset value will improve the funding ratio, but contributions are still insufficient to cover benefit payouts.
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| 3. |
- Ndanguza, Denis, et al.
(författare)
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Bayesian inference approach in modeling and forecasting maize production in Rwanda
- 2018
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Ingår i: African Journal of Applied Statistics. - : Statistics and Probability African Society (SPAS). - 2316-0861. ; 5:2, s. 503-517
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Tidskriftsartikel (refereegranskat)abstract
- Rwanda is the country whose economy relies on agriculture. Therefore,forecast in agriculture sector is very important in Rwanda for future plan. In ourstudy, secondary annual data from the agricultural ministry (MINAGRI), spanningfrom 1960 to 2014 have been used. In the analysis, appropriate model is selectedbased on the appearance of ACF and PACF of the transformed data. In addition tothat, we use the fitted model to provide a four year forecasts of maize productionfrom 2015 to 2018. Through Box–Jenkins methodology, the appropriate model isARIMA (1,2,1) and fit the data at 91%. From the results and forecast, it is seen thatthe production of maize in Rwanda will have an increasing trend in the future. Tostrengthen the model, we also use the MCMC algorithm as an alternative methodin parameters estimation. Diagnostics prove the chains’ convergence which is thesign of an accurate model.
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| 4. |
- Ngaruye, Innocent, et al.
(författare)
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Crop yield estimation at district level for agricultural seasons 2014 in Rwanda
- 2016
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Ingår i: African Journal of Applied Statistics. - : Statistics and Probability African Society (SPAS). - 2316-0861. ; 3:1, s. 69-90
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we discuss an application of Small Area Estimation (SAE) tech- niques under a multivariate linear regression model for repeated measures data to produce district level estimates of crop yield for beans which comprise two varieties, bush beans and climbing beans in Rwanda during agricultural seasons 2014. By using the micro data of National Institute of Statistics of Rwanda (NISR) obtained from the Seasonal Agricul- tural Survey (SAS) 2014 we derive efficient estimates which show considerable gain. The considered model and its estimates may be useful for policy-makers or for further analyses.
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