文摘
Let \((X_n)\) be a sequence of independent and identically distributed random variables, with common absolutely continuous distribution \(F\). An observation \(X_n\) is a near-record if \(X_n\in (M_{n-1}-a,M_{n-1}]\), where \(M_{n}=\max \{X_1,\ldots ,X_{n}\}\) and \(a>0\) is a parameter. We analyze the point process \(\eta \) on \([0,\infty )\) of near-record values from \((X_n)\), showing that it is a Poisson cluster process. We derive the probability generating functional of \(\eta \) and formulas for the expectation, variance and covariance of the counting variables \(\eta (A), A\subset [0,\infty )\). We also obtain strong convergence and asymptotic normality of \(\eta (t):=\eta ([0,t])\), as \(t\rightarrow \infty \), under mild tail-regularity conditions on \(F\). For heavy-tailed distributions, with square-integrable hazard function, we show that \(\eta (t)\) grows to a finite random limit \(\eta (\infty )\) and compute its probability generating function. We apply our results to Pareto and Weibull distributions and include an example of application to real data.