**2.5 The issue of the complexity of interconnected information systems**

Today's era is characterized by a very dynamic exchange of data/information that is essential for correct and timely decision-making. Vehicle data is stored in various information systems so that it is necessary to link diverse information systems to obtain a comprehensive picture of the overall situation (**Figures 6** and **7**). In the case of vehicles, the linking key is the VIN. The VIN is globally unique and is physically located on the vehicle at several standardized locations so that it is always possible to link the physical identity of the vehicle to its identity in the information systems. The quality of the VIN entry in each information system separately then determines the searchability of all the interlinked information systems.

### **2.6 What is the quality (Error Rate) of the VIN in the information systems?**

This was a fundamental question that was one of the main objectives of the research conducted. The research was carried out on a data sample of 4 million vehicles from the Vehicle Inspection Register managed by the Ministry of Transport of the Czech Republic. This system is characterized by the fact that no checks are carried out when a vehicle roadworthiness test is entered. The VIN is copied manually from the vehicle document presented for technical inspection, without any check in the information system against any previous inspections of the same vehicle, without any technical means of obtaining the VIN from the vehicle or its documents. Nor is there any check of the existence of the vehicle being checked against the national vehicle register. There is also no check on the formal, logical structure of the VIN (length of the VIN string and prohibited characters) and no calculation of the check digit either.

Using the VINdecoder application (VINexpert), every record of the 4 million record sample set was batch analyzed. Each VIN of all the vehicles in the Czech Vehicle Inspection Register was examined and evaluated for its decodability and

#### **Figure 6.**

*The possibilities of linking vehicle data between different information systems, both nationally and internationally, can be seen as complex networks of different links, the basis of which is an error-free VIN. Any error (intentional or unintentional) means a failure in the efficiency and comprehensiveness of the vehicle information provided. Source: Roman Rak.*


#### **Figure 7.**

*Example of display of errors found in a vehicle identifier. Source: Roman Rak.*

checked for correctness. If any decoding was incorrect, the causes were sought. The final report featured the statuses for every record listed in **Table 1**.
