Articles | Nigerian Journal of Mathematics and Applications

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Research Article DOI: 10.67897/njma.2026.xa92ictk

On Specification of Almon Distribued Lag Model in the Presence of Multicollinearity

T. K. Ajetunmobi, O. K. Agunloye^*

In Almon distributed lag modeling, presence of multicollinearity, choice of appropriate approximating polynomial of suitable degree and choice of optimal truncation lag-length required for the implementation of Almon distributed lag model constitute three major problems confronting Almon distributed lag modeling.Given the fact that the choice of appropriate approximating polynomial of suitable deg...

Jun, 2026 pp. 81-91 17 views 4 downloads

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Research Article DOI: 10.67897/njma.2026.7uel8ksq

Monitoring CSM in Northern Nigeria: A Logistic and OLS Regression Approach

S. O. Elakhe, Rofiyat Patience Braimah, d I. W. Edokpa, J. O. Braimah^*

Cerebrospinal meningitis (CSM) remains a major public health challenge in sub-Saharan Africa. This study analyzed records of 390 suspected CSM patients (2020–2023) from Aminu Kano Teaching Hospital, Nigeria, using sex, age, and month as explanatory variables. Logistic regression and ordinary least square (OLS) models were fitted to identify epidemic patterns. Findings reveal that children under fi...

Jun, 2026 pp. 63-80 16 views 5 downloads

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Research Article DOI: 10.67897/njma.2026.mq7kkwxh

Two-Dimensional Laminar Boundary Layers Hydromagnetic Arrhenius Kinetics Dissipative Fluid Reactive Flow in Non-Slip Conditions with Variable Properties

R. A. Kareem^*, L. A. Animashaun, J. O. Ajilore

This study investigates non-slip hydromagnetic laminar dissipation flow with Arrhenius kinetics in binary reactions characterized by reaction order and variable properties within an unbounded isothermal device. The partial differentiation model is nondimensionalized to a thermofluidic dimensionless form. An invariant quasi-linear coupled ordinary derivative model is obtained using similarity quant...

Jun, 2026 pp. 47-62 25 views 6 downloads

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Research Article DOI: 10.67897/njma.2026.phtju71m

A Halpern Resolvent-Subgradient-Extragradients Method for finding common solution of fixed point, h-fixed point, equilibrium and variational inequality problems in Banach spaces

Enyinnaya Ekuma-Okereke^*, Joseph O. Ogbodu

The key idea behind solving well known applicable problems is to reformulate the problems as finding a fixed point of a suitably defined mapping. The theory of variational inequalities and equilibrium problems involving some operators with monotonicity conditions have received remarkable development with several methods suggested for solving them. Efforts have significantly been made in approximat...

Jun, 2026 pp. 31-46 21 views 15 downloads

5

Research Article DOI: 10.67897/njma.2026.fqssihod

Tian Invariants on G2,4(C) Blown Up Along P1(C) ∼= S2

Riadh JELLOUL^*

In this paper, we prove the existence of an extremal functionthat minorizes all admissible functions with zero supremum ona non-toric Fano manifold, namely the complex GrassmannianG2,4(C) blown up along P1(C). The functions considered areinvariant under a suitably chosen automorphism group. Thislower bound allows us to calculate the Tian invariant for this classof functions on these manifolds. Mor...

Apr, 2026 pp. 15-30 30 views 9 downloads

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Research Article DOI: 10.67897/njma.2026.1aweh9n9

Efficiency of Simpson’s Rule; A Case Study of Unilorin Land Area

Ayinla Ally Yeketi^*, Isola Olatomiwa Oluwadamilare

Simpson’s rule, a numerical integration technique, provides anefficient method for estimating the area of an irregularly shapedlarge landmasses when analytical solutions are impractical. Thisstudy applies Simpson’s 13 , 38 and hybrid rules to determine thearea of the University of Ilorin landmass. The hybrid method,combining the 13 and 38 rules, proves to be more efficient due to itsflexibility wi...

Apr, 2026 pp. 8-14 24 views 9 downloads

7

Research Article DOI: 10.67897/njma.2026.274l2dsn

Radial Solution of the Monge-Amp`ere Equation on R3 and R4

Riadh JELLOUL^*

In this paper, we determine radial solutions of the Monge-Amp`ere equation on R3 and R4 using a symplectic changeof variables. This transformation simplifies the formulationof the equation and allows it to be expressed in radialform, thereby reducing the problem to an associated ordinarydifferential equation. The existence and uniqueness of thesolutions are established and explicit expressions are...

Apr, 2026 pp. 1-7 25 views 11 downloads

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Research Article DOI: 10.67897/njma.2025.auppw045

Tian Invariant on the Blown-up Grassmannian Futaki Obstructions and K-Stability

Riadh JELLOUL^*

In this paper, we compute the Tian invariant on a generalization of Calabi manifolds introduced by the author in collaboration with A. Ben Abdesselem and M. Filali in [1]. We adapt the method of the original article to the setting of complex Grassmannians blown up along linear subvarieties. Our original contribution is fourfold: we explicitly determine the subgroup H ⊂ Aut(G(k, n)) = P GL(n, C) th...

Jun, 2025 pp. 92-111 16 views 3 downloads

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Research Article DOI: 10.67897/njma.2025.4ciazhok

Forecasting Monthly Inflation Rate in Nigeria Using Causal and Invertible Autoregressive Moving Average Models

O. K. Agunloye^*, K. A. Alamu

This paper evaluates causal and invertible ARMA models for forecasting Nigeria’s inflation rate. After testing stationarity and fitting candidates, the ARMA(1, 4) model emerged as optimal. It satisfies causality, invertibility, and outperforms alternatives across loss functions.

Jun, 2025 pp. 82-90 7 views 2 downloads

10

Research Article DOI: 10.67897/njma.2025.bu0d8o9t

Polynomial Bounds for Bi-Univalent Functions Associated with Sigmoid Function and Q− Derivative Over a Chebyshev Polynomials

I. T. Awolere, A. M. Gbolagade^*

This paper introduces a new subclass of the function class P of biunivalent analytic functions defined in the open unit disk, associated with a certain operator and the Sigmoid function via Chebyshev polynomials. Bounds for the initial coefficients are obtained for the defined class, along with results for the Fekete–Szeg¨o functional. Furthermore, by varying the parameters involved, several resul...

Jun, 2025 pp. 71-81 10 views 2 downloads