Qualification of the results of aggregated lean KPIs along fuzzy logic

Abstract

The application of lean management has become a fundamental competitive criterion in the operation of industrial enterprises in the 21st century. The use of tools and methods related to different lean management appears in a significant part of corporate functions. However, it is also important to mention that these lean tools and methods are used in addition to the mixed use of many other tools and methods that support non-lean goals. This problem is also a challenge for controlling. Because lean accounting methods do not necessarily measure the extent of lean effectively in such an environment, a number of other methods are used to monitor lean in both academic and business practice. Of these, lean evaluation models based on fuzzy logic should be highlighted. With the help of these models, it is possible to determine the lean performance of a company primarily along financial data. The disadvantage of the model, however, is that lean management also appears in a number of functional areas that cannot be assessed along financial ratios, but they clearly influence the operation of lean management.
 In our research, we illustrated a complex set of lean controlling methods through an instrumental case study, which allows companies to evaluate the performance of lean management and to explore different points of intervention. Our research results make it possible to calculate the lean fuzzy index not only along financial data, and thus clarify the information content of the index. Along the methods and indicators formulated in our research, the effectiveness of lean methods and tools, as well as the processes and methods supporting lean goals, can be separated and measured. Our research goal is to create a generally applicable lean controlling conceptual model.