TY - JOUR AU - Ding, Juan AU - Zhou, Chi AU - Xia, Anqi AU - Zhou, Wenxin AU - Xiong, Wenjun PY - 2026 TI - A two-parameter family of Hollander–Proschan–type tests against NBUE alternatives JO - AIMS Mathematics SP - 13567 EP - 13588 VL - 11 IS - 5 AB - Testing for aging behavior is a fundamental problem in reliability analysis. We study tests of exponentiality against new better than used in expectation (NBUE) alternatives. Many Hollander–Proschan type procedures can be interpreted as weighted functionals of a common mean residual life gap, but are often presented in isolated forms, making it difficult to understand how weighting affects sensitivity to different alternatives. We develop a unified weighted-functional framework in which several classical procedures arise as special or limiting cases. Within this framework, we construct a centered and studentized statistic with an asymptotic normal null distribution and an explicit centering term. Pitman efficiency analysis and Monte Carlo experiments illustrate how weighting influences sensitivity and finite-sample performance, while real-data applications demonstrate practical interpretability. UR - https://doi.org/10.3934/math.2026558 DO - 10.3934/math.2026558