Social Network Analysis in Encouraging Role-Players in the Beef Market to Take Breeding Decisions: A Methodological Study

Figures & data

Figure 1. The structure of the inquiry.

Figure 2. Supply side and procurement side competition in the network.

Figure 3. Romagnola meat (slaughtered heifers) supply chain: agents’ networks.

Figure 4. Agents’ position according to hub and authority.

Figure 5. Cohesive blocking for the network of role-players involved in Romagnola exchanges.

Table 1. Empirical measurements of the agent’s interaction.

Variable	Measurement	Meaning
Cohesion	Density	Effective ties respect to the potential ones, given the number of total agents.
	Distance	The shorter length connecting 2 agents.
Centrality	Degree	Number of adjacent nodes.
	Closeness	Sum of the distances between a node and the remaining nodes.
	Betweenness	The frequency according to which a given node appears within the shorter path between 2 nodes.
Competitive position	Coordinate u	The number of suppliers in competition with the company.
	Coordinate v	The number of buyers in competition with the company.
SCA		Minimum number of role-players who, if removed from the group, would disconnect the group.

Table 2. Centrality: largest values of the networks. Only the largest values of each index are reported with the descriptive statistical indexes and the overall network measurements.

Agents	Degree of centralisation	Agents	Closeness	Agents	Betweenness Centrality
ALL3	43	ALL3	62.1	ALL3	2123.4
LAB5	38	INT5	56.6	LAB5	1288.7
INT5	38	INT1	56.2	INT5	927.8
LAB8	21	LAB8	49.7	LAB4	680.8
INT6	21	INT6	48.1	INT1	650.4
Mean	9.2		41.7		98.1
SD	7.9		6.01		310.8
Network centralisation	45.1		41.6		35.1

ALL, breeders; LAB, industrial meat processing plants; INT, marketing companies; SD, standard deviation.

Table 3. Effect of nestedness on the product flow.

Effect	Coef.±SE	P>t
ALL	51.71±26.19	0.05
LAB	-16.98±10.38	0.41
DEST	-38.04±16.98	0.03
Nestedness	4.85±1.15	0.00
Constant	3.95±19.15	0.84
R-squared model	0.30