STATISTICAL REANALYSIS OF PUBLISHED EVIDENCE FROM DELTA STATE, NIGERIA ON OWNERSHIP, INCENTIVES, AND TRACTOR SERVICEABILITY

Abstract

This study assessed the association between tractor ownership type and serviceability in agricultural tractor fleets in Delta State, Nigeria. Published aggregate data comprising 89 tractors from 16 agricultural locations, including 60 state-owned and 29 privately owned tractors, were reanalysed using a 2 × 2 contingency table. A Pearson chi-square test of independence was used to determine whether ownership type was significantly associated with tractor serviceability, while the odds ratio with a 95% confidence interval and Cramér's V were used to quantify the magnitude and strength of the association. The analysis showed a statistically significant association between ownership type and tractor serviceability (χ² = 22.40, df = 1, p < 0.001). Privately owned tractors were 10.33 times more likely to be serviceable than state-owned tractors (95% CI: 3.65–29.21), with a Cramér's V of 0.50, indicating a large effect. Private tractors also recorded higher mean annual working hours (572.6 h/year) than state-owned tractors (189.0 h/year), yet exhibited substantially higher serviceability. The findings indicate that ownership type is strongly associated with tractor serviceability in the assessed fleet and suggest that differences in maintenance incentives and institutional accountability may contribute to the observed disparity. The study concludes that improving accountability and maintenance management in state-operated tractor fleets may be important for enhancing tractor availability and serviceability.