Table 3 Cross-year analysis of network... | Emerald Publishing

Table 3

Cross-year analysis of network characteristics

	1996	2005	2015	2020	2023
Node centrality	- The OEM’s degree centrality increases from 1996 to 2023 (3–22) and closeness centrality decreases (0.111–0.031); betweenness remains the highest in the network (0.6) - Tier 1 suppliers’ average degree centrality does not change (∼2.33) but closeness centrality (0.089–0.018) and betweenness centrality decrease strongly (0.2–0.01) from 1996 to 2023 - The semiconductor suppliers’ highest degree centrality increases (SS3, from 2 in 1996 to 14 in 2023), but closeness centrality decreases considerably (0.077–0.024); the highest betweenness centrality decreases (0.067–0.17) while many semiconductor suppliers have betweenness centrality close to 0
	- Lack of connections between OEM and semiconductor suppliers - Tier 1 suppliers have central position to control and connect upstream and downstream	- OEM’s decision to use one semiconductor family across its ECUs enables SS3’s growing degree centrality starting from 2005 - Stronger links are created with specific semiconductor suppliers (OEM1 - SS3)	- Degree centrality of OEM and semiconductor suppliers increase due to new connections with Tier 1 suppliers - Emergence of new, disconnected nodes (ADs, EMs) - A gap is created in linking innovation needs and possibilities between OEMs and semiconductor suppliers	- Tier 1 suppliers cannot coordinate supply and demand for semiconductors due to demand fluctuations and semiconductor shortages	- OEMs make direct connections with semiconductor suppliers connections aiming to secure supply by increasing information sharing - Information flows are still restricted by confidentiality terms of contracts with Tier 1 suppliers
Network complexity	- Network size increases from 7 to 28, and density decreases from 0.33 to 0.14 - Continuous network growth due to the need for new ECUs - The entrance of new Tier 1 suppliers outweighs mergers and acquisitions between Tier 1 suppliers - Addition of new, increasingly disconnected nodes - During all years except 2023, all connections passed through Tier 1 suppliers - No cooperation between nodes of the same type: each ECU has one responsible Tier 1 supplier, which is connected to other nodes needed for that ECU
	- Small number of ECUs in vehicles - Few Tier 1 suppliers are able to meet ECU vibration test requirements - Monopoly-like position of those few Tier 1 suppliers	- High network density	- Entrance of Tier 1 suppliers previously specialized in mechanical parts - First appearance of ADs and EMS companies in the network	- The network achieves its peak size with the entrance of new nodes in all node types	- Network density slightly increases due to new connections across the network
Network centralization	- Degree centralization of the network increases from 0.23 to 0.72 - Unique information paths for each ECU makes the Tier 1 supplier the central actor in each ECU’s supply chain - Increasing centralization represents the high centrality of the OEM, while in reality, power is centered around Tier 1 suppliers
	OEMs’ active decision not to design ECUs but rather rely on Tier 1 suppliers for that task	–	Lack of resources and semiconductor knowledge stopped OEMs from involvement with semiconductor suppliers, despite growing value of semiconductors in vehicles	–	–

	1996	2005	2015	2020	2023
Node centrality	- The OEM’s degree centrality increases from 1996 to 2023 (3–22) and closeness centrality decreases (0.111–0.031); betweenness remains the highest in the network (0.6) - Tier 1 suppliers’ average degree centrality does not change (∼2.33) but closeness centrality (0.089–0.018) and betweenness centrality decrease strongly (0.2–0.01) from 1996 to 2023 - The semiconductor suppliers’ highest degree centrality increases (SS3, from 2 in 1996 to 14 in 2023), but closeness centrality decreases considerably (0.077–0.024); the highest betweenness centrality decreases (0.067–0.17) while many semiconductor suppliers have betweenness centrality close to 0
	- Lack of connections between OEM and semiconductor suppliers - Tier 1 suppliers have central position to control and connect upstream and downstream	- OEM’s decision to use one semiconductor family across its ECUs enables SS3’s growing degree centrality starting from 2005 - Stronger links are created with specific semiconductor suppliers (OEM1 - SS3)	- Degree centrality of OEM and semiconductor suppliers increase due to new connections with Tier 1 suppliers - Emergence of new, disconnected nodes (ADs, EMs) - A gap is created in linking innovation needs and possibilities between OEMs and semiconductor suppliers	- Tier 1 suppliers cannot coordinate supply and demand for semiconductors due to demand fluctuations and semiconductor shortages	- OEMs make direct connections with semiconductor suppliers connections aiming to secure supply by increasing information sharing - Information flows are still restricted by confidentiality terms of contracts with Tier 1 suppliers
Network complexity	- Network size increases from 7 to 28, and density decreases from 0.33 to 0.14 - Continuous network growth due to the need for new ECUs - The entrance of new Tier 1 suppliers outweighs mergers and acquisitions between Tier 1 suppliers - Addition of new, increasingly disconnected nodes - During all years except 2023, all connections passed through Tier 1 suppliers - No cooperation between nodes of the same type: each ECU has one responsible Tier 1 supplier, which is connected to other nodes needed for that ECU
	- Small number of ECUs in vehicles - Few Tier 1 suppliers are able to meet ECU vibration test requirements - Monopoly-like position of those few Tier 1 suppliers	- High network density	- Entrance of Tier 1 suppliers previously specialized in mechanical parts - First appearance of ADs and EMS companies in the network	- The network achieves its peak size with the entrance of new nodes in all node types	- Network density slightly increases due to new connections across the network
Network centralization	- Degree centralization of the network increases from 0.23 to 0.72 - Unique information paths for each ECU makes the Tier 1 supplier the central actor in each ECU’s supply chain - Increasing centralization represents the high centrality of the OEM, while in reality, power is centered around Tier 1 suppliers
	OEMs’ active decision not to design ECUs but rather rely on Tier 1 suppliers for that task	–	Lack of resources and semiconductor knowledge stopped OEMs from involvement with semiconductor suppliers, despite growing value of semiconductors in vehicles	–	–

Source(s): Created by the authors