A Multi-Gene Genetic Programming Application for Predicting Students Failure at School

Several efforts to predict student failure rate (SFR) at school accurately still remains a core problem area faced by many in the educational sector. The procedure for forecasting SFR are rigid and most often times require data scaling or conversion into binary form such as is the case of the logistic model which may lead to lose of information and effect size attenuation. Also, the high number of factors, incomplete and unbalanced dataset, and black boxing issues as in Artificial Neural Networks and Fuzzy logic systems exposes the need for more efficient tools. Currently the application of Genetic Programming (GP) holds great promises and has produced tremendous positive results in different sectors. In this regard, this study developed GPSFARPS, a software application to provide a robust solution to the prediction of SFR using an evolutionary algorithm known as multi-gene genetic programming. The approach is validated by feeding a testing data set to the evolved GP models. Result obtained from GPSFARPS simulations show its unique ability to evolve a suitable failure rate expression with a fast convergence at 30 generations from a maximum specified generation of 500. The multi-gene system was also able to minimize the evolved model expression and accurately predict student failure rate using a subset of the original expressionComment: 14 pages, 9 figures, Journal paper. arXiv admin note: text overlap with arXiv:1403.0623 by other author

Can Higher Inflation Lead to Currency Appreciation in Nigeria?

This work verified if higher inflation can lead to currency appreciation in Nigeria using an annual data from 1981 to 2013. The ordinary least square (OLS) method was adopted because of its best linear unbiased estimator property. The result showed that current inflation does not lead to currency appreciation in Nigeria, and rather what leads to currency appreciation is expected inflation. Although, monetary policy rate and export were significant in determining Naira value but they did not show the expected signs. The estimated model showed stability and all the explanatory variables used for the analysis accounted for 96% variation in explaining the direction of value of Naira as regards to appreciation or depreciation. The co-integration test showed that a long term relationship existed among the variables and they were stationary at order one I (1). Keywords: Currency, Inflation, Co-integration and Appreciatio

Modeling the effect of KCL inhibition on the rheological properties of shale contaminated water based mud.

Water based muds are the most extensively used drilling muds. Their use is however limited, especially in shaley formations where it results to various degrees of wellbore instability. In such formations, oil based muds are often utilized due to their possession of superior shale stabilization properties. The recent emphasis on environmental protection, high cost of formulation and disposal after use, amongst other factors however, present huge challenges to the use of oil based muds thereby resulting to a pressing need for the design of water based muds that can be adapted to suit the drilling of such problematic formations. Use of potassium based (i.e. KCl) inhibition has been found to be successful in areas where inhibition is required to limit chemical alteration of shales, the challenge then becomes the development of efficient means of formulating such mud systems. In this paper, experimental data is used to establish the fact that rheological properties of a water based mud (plastic viscosity and yield point) are altered when shaley formation is encountered and use of KCl inhibition can correct this problem as it tends to return the properties to their original values. Furthermore, equations which can be used to predict the changes in rheological properties as shale concentration increases and effect of utilizing inhibition are developed using the obtained data with reasonable accuracy

An Isocurvature CDM Cosmogony. II. Observational Tests

A companion paper presents a worked model for evolution through inflation to initial conditions for an isocurvature model for structure formation. It is shown here that the model is consistent with the available observational constraints that can be applied without the help of numerical simulations. The model gives an acceptable fit to the second moments of the angular fluctuations in the thermal background radiation and the second through fourth moments of the measured large-scale fluctuations in galaxy counts, within the possibly significant uncertainties in these measurements. The cluster mass function requires a rather low but observationally acceptable mass density, 0.1\lsim\Omega\lsim 0.2 in a cosmologically flat universe. Galaxies would be assembled earlier in this model than in the adiabatic version, an arguably good thing. Aspects of the predicted non-Gaussian character of the anisotropy of the thermal background radiation in this model are discussed.Comment: 14 pages, 3 postscript figures, uses aas2pp4.st

WMAP constraints on the Intra-Cluster Medium

We devise a Monte-Carlo based, optimized filter match method to extract the thermal Sunyaev-Zel'dovich (SZ) signature of a catalog of 116 low-redshift X-ray clusters from the first year data release of the Wilkinson Microwave Anisotropy Probe (WMAP). We detect an over-all amplitude for the SZ signal at the ~ 8-sigma level, yielding a combined constraint of f_{gas}h = 0.08 +/- 0.01 (ran) +/- 0.01 (sys) on the gas mass fraction of the Intra-Cluster Medium. We also compile X-ray estimated gas fractions from the literature for our sample, and find that they are consistent with the SZ estimates at the 2-sigma level, while both show an increasing trend with X-ray temperature. Nevertheless, our SZ estimated gas fraction is 30-40% smaller than the concordance LCDM cosmic average. We also express our observations in terms of the SZ flux-temperature relation, and compare it with other observations, as well as numerical studies. Based on its spectral and spatial signature, we can also extract the microwave point source signal of the clusters at the 3-sigma level, which puts the average microwave luminosity (at ~ 41 GHz) of bright cluster members (M_K < -21) at (2.4 +/- 0.8) x 10^{27} h^{-2} erg/s/Hz. Furthermore, we can constrain the average dark matter halo concentration parameter to c_{vir}=3.4+0.6-0.9, for clusters with T_x > 5 kev. Our work serves as an example for how correlation of SZ surveys with cluster surveys in other frequencies can significantly increase our physical understanding of the intra-cluster medium.Comment: 34 pages, 6 ps figures, Extended discussion of theoretical uncertainties, radio sources, and future prospects, Accepted for Publication in Ap