Fraud cycles

Fraud is an ancient crime and one that annually causes hundreds of billions of dollars in losses. We examine the behavioral patterns over time of different types of frauds, which illustrate cyclical frequencies. We develop an evolutionary theory that suggests cyclic behavior in frauds should be common.fraud, cycle, steady state

Inventory performance under staggered deliveries and autocorrelated demand

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordProduction plans often span a whole week or month, even when independent production lots are completed every day and service performance is tallied daily. Such policies are said to use staggered deliveries, meaning that the production rate for multiple days are determined at a single point in time. Assuming autocorrelated demand, and linear inventory holding and backlog costs, we identify the optimal replenishment policy for order cycles of length P. With the addition of a once-per-cycle audit cost, we optimize the order cycle length P∗ via an inverse-function approach. In addition, we characterize periodic inventory costs, availability, and fill rate. As a consequence of staggering deliveries, the inventory level becomes cyclically heteroskedastic. This manifests itself as ripples in the expected cost and service levels. Nevertheless, the cost-optimal replenishment policy achieves a constant availability by using time-varying safety stocks; this is not the case with suboptimal constant safety stock policies, where the availability fluctuates over the cycle

Basics of inventory management (Part 5: The (R,b,Q)-model)

Inventory Models;management science

Calculation of an approximate solution of the infinite time-varying LQ-problem

Linear Programming;Algorithm;Optimal Control;operations research

Density of the least squares estimator in the multivariate linear model with arbitrarily normal variables

Estimation;Multivariate Analysis;statistics

The covariance matrix of ARMA-errors in closed form

Matrices;mathematics

Fault Detection and Diagnosis for Compliance Monitoring in International Supply Chains

Currently international supply chains are facing risks concerning faults in compliance, such as altering shipping documentations, fictitious inventory, and inter-company manipulations. In this paper a method to detect and diagnose fault scenarios regarding customs compliance in supply chains is proposed. This method forms part of a general approach called model-based auditing, which is based on a normative meta-model of the movement of money and goods or services. The modeling framework is proposed on compliance monitoring of supply chains with focus on information systems and compliance reporting tools. The innovation lies in the application and mapping of modeling techniques from dynamical systems engineering to business process analysis for audit and supervision purposes. Specifically, the application domain is where money, goods as well as information are transferred between international supply chain partners. A case study of a leading company in electronics manufacturing applying the model is analyzed

Free end-point linear-quadratic control subject to implicit continuous-time systems: Necessary and sufficient conditions for solvability

Optimal Control;operations research

Basics of inventory management (Part 6: The (R,s,S)-model)

Inventory Models;management science