Improving expected shortage estimations in the base-stock policy by accounting for undershoots

Shortage events are inevitable random phenomena in inventory systems when dealing with real demand. For inventory managers, knowing the size of these shortages becomes crucial to deciding the optimal policy for the inventory system. Therefore, the Expected Shortage per Replenishment Cycle, ESPCR, is...

Full description

Saved in:
Bibliographic Details
Main Authors: Eugenia Babiloni, Ester Guijarro
Format: Article
Language:English
Published: Universitat Politècnica de València 2025-01-01
Series:International Journal of Production Management and Engineering
Subjects:
Online Access:https://polipapers.upv.es/index.php/IJPME/article/view/22044
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832576012794200064
author Eugenia Babiloni
Ester Guijarro
author_facet Eugenia Babiloni
Ester Guijarro
author_sort Eugenia Babiloni
collection DOAJ
description Shortage events are inevitable random phenomena in inventory systems when dealing with real demand. For inventory managers, knowing the size of these shortages becomes crucial to deciding the optimal policy for the inventory system. Therefore, the Expected Shortage per Replenishment Cycle, ESPCR, is an essential indicator in inventory management for several reasons. On the one hand, it gives information about the number of units not served in each cycle, and on the other hand, it is fundamental in determining service levels or shortage costs. Therefore, ESPCR estimation for the continuous review base-stock policy (s, S) is traditionally based on the assumption that inventory levels reach exactly the reorder point, i.e., inventory levels are never below the reorder point, and undershoots are not considered. This paper shows that the traditional estimation based on neglecting undershoots is biased and proposes a new and unbiased approximation, ESPCRW. This approach is based on estimating the probability vector of the stock levels at the reorder point considering the presence of undershoots. Results of this paper show that our approach outperforms the biased nature of the traditional approximation, which may have significant practical implications for the inventory systems.
format Article
id doaj-art-c31ac4270b5a4958a9425c964a5dd602
institution Kabale University
issn 2340-4876
language English
publishDate 2025-01-01
publisher Universitat Politècnica de València
record_format Article
series International Journal of Production Management and Engineering
spelling doaj-art-c31ac4270b5a4958a9425c964a5dd6022025-01-31T13:48:47ZengUniversitat Politècnica de ValènciaInternational Journal of Production Management and Engineering2340-48762025-01-011319310110.4995/ijpme.2025.2204421234Improving expected shortage estimations in the base-stock policy by accounting for undershootsEugenia Babiloni0https://orcid.org/0000-0002-7949-3703Ester Guijarro1https://orcid.org/0000-0003-1988-0397Universitat Politècnica de ValènciaUniversitat Politècnica de València Shortage events are inevitable random phenomena in inventory systems when dealing with real demand. For inventory managers, knowing the size of these shortages becomes crucial to deciding the optimal policy for the inventory system. Therefore, the Expected Shortage per Replenishment Cycle, ESPCR, is an essential indicator in inventory management for several reasons. On the one hand, it gives information about the number of units not served in each cycle, and on the other hand, it is fundamental in determining service levels or shortage costs. Therefore, ESPCR estimation for the continuous review base-stock policy (s, S) is traditionally based on the assumption that inventory levels reach exactly the reorder point, i.e., inventory levels are never below the reorder point, and undershoots are not considered. This paper shows that the traditional estimation based on neglecting undershoots is biased and proposes a new and unbiased approximation, ESPCRW. This approach is based on estimating the probability vector of the stock levels at the reorder point considering the presence of undershoots. Results of this paper show that our approach outperforms the biased nature of the traditional approximation, which may have significant practical implications for the inventory systems.https://polipapers.upv.es/index.php/IJPME/article/view/22044inventorycontinuous reviewexpected shortage per replenishment cyclelost salesundershoots
spellingShingle Eugenia Babiloni
Ester Guijarro
Improving expected shortage estimations in the base-stock policy by accounting for undershoots
International Journal of Production Management and Engineering
inventory
continuous review
expected shortage per replenishment cycle
lost sales
undershoots
title Improving expected shortage estimations in the base-stock policy by accounting for undershoots
title_full Improving expected shortage estimations in the base-stock policy by accounting for undershoots
title_fullStr Improving expected shortage estimations in the base-stock policy by accounting for undershoots
title_full_unstemmed Improving expected shortage estimations in the base-stock policy by accounting for undershoots
title_short Improving expected shortage estimations in the base-stock policy by accounting for undershoots
title_sort improving expected shortage estimations in the base stock policy by accounting for undershoots
topic inventory
continuous review
expected shortage per replenishment cycle
lost sales
undershoots
url https://polipapers.upv.es/index.php/IJPME/article/view/22044
work_keys_str_mv AT eugeniababiloni improvingexpectedshortageestimationsinthebasestockpolicybyaccountingforundershoots
AT esterguijarro improvingexpectedshortageestimationsinthebasestockpolicybyaccountingforundershoots