The International Journal in Economics and Business Strategies
Volume 5, Numéro 2, Pages 30-38
2025-12-31

Ridge Regression For Analysing The Determinants Of Co₂ Emissions In Algeria Under ‎multicollinearity (1970–2018)‎

Authors : ‎souhila ‎lazali . Fatiha Mezoued .

Abstract

Abstract: ‎ This study applies Ridge regression to analyse the economic and demographic determinants of ‎CO₂ emissions in Algeria over the period 1970–2018, in the presence of severe multicollinearity ‎that undermines the properties of the Ordinary Least Squares (OLS) estimator. The explanatory ‎variables include GDP per capita, energy use per capita, foreign direct investment, total ‎population, and urbanisation rate, within a log-log specification. Multicollinearity diagnostics ‎reveal VIF values exceeding 160 for most regressors and a condition number of 37.74, rendering ‎OLS estimates highly unstable. The shrinkage parameter k is selected via ten-fold cross-‎validation; Ridge regression achieves CV-MSE = 0.0206, representing a 19.1% improvement over ‎OLS. Energy use per capita emerges as the sole statistically significant determinant (elasticity = ‎‎0.479; p < 0.01), reflecting Algeria's heavy dependence on fossil fuels.‎

Keywords

Keywords: Ridge regression, multicollinearity, CO₂ emissions, Algeria, bias-variance trade-‎off, cross-validation.‎