Where does structural holes collide?

Burt's structural holes are the gaps between two contacts who are not connected to each other, so that a person tied to both spans a hole in the surrounding network. In Structural Holes (1992) Burt argued that these gaps are opportunities: a broker who bridges otherwise disconnected groups sees information earlier, sees it from more angles, and can shape what passes between the two sides. The pay-off shows up in careers and ideas, so managers whose networks were rich in holes tended to be promoted faster and paid more. In Structural Holes and Good Ideas (2004) Burt reported that people who spanned holes between groups were more likely to voice ideas that others rated as valuable. The referent is a pattern of missing ties around a person, and its value comes from the non-redundancy of what the two sides know.[1][2]

Unit

A pattern of missing ties around a person, by the non-redundant contacts they hold apart

Recovery means

Not applicable

Measured by

Read from ego networks as the number and non-redundancy of a person's disconnected contacts, against career or idea outcomes

When the brokerage idea is turned into a number, two operationalizations compete. Freeman's betweenness centrality (1977) counts how often a node lies on the shortest path between other pairs of nodes, so a broker scores high when removing them would cut many others off from each other. Burt's network constraint runs the other way: it is low when a person's contacts are disconnected among themselves, so a low-constraint node is rich in structural holes. Both are computed from the same adjacency matrix, but one rewards sitting on paths and the other rewards having contacts who do not know each other, and they need not agree on who the brokers are. Here the broker is a quantity read off a graph, not a story told about a person.[3][1]

Unit

A node's brokerage position in a graph, as a centrality or constraint score

Recovery means

Not applicable

Measured by

Computed from the adjacency matrix as betweenness centrality (Freeman) or as network constraint (Burt)

In the economic reading, brokerage is arbitrage: a person or firm that stands between two sides who cannot easily reach each other can profit from the gap between them. Burt took the figure of the tertius gaudens, the third who benefits, from Simmel, and applied it to the broker who plays disconnected parties against one another or simply charges for the connection. The advantage here is control and rent rather than information, because the broker's leverage comes from being the only path between buyers and sellers, or between two groups that do not trade directly. Stovel and Shaw's 2012 review follows this reading across labour markets, trade, and organizations, and notes that the same position that yields profit can also draw distrust. The referent is a market gap that a middleman monetizes, close in spirit to the structural hole but named for the gain rather than the gap.[1][4]

Unit

A middleman's position between two sides who do not trade directly

Recovery means

Not applicable

Measured by

Inferred from who must pass through the broker, and from the rent or margin the position earns

In diffusion and communication research the same position is named for what crosses it: a bridge is a tie that provides the only route between two clusters, so information passing between them must travel through it. Granovetter's 1973 argument was that such bridges tend to be weak ties, because strong ties fold back into a person's own dense group, and so novel information often reaches people through their weaker, bridging contacts. The broker here is valued as a conduit, a channel through which ideas, jobs, or practices spread from one part of a network to another. This is close to the structural-hole reading, but its emphasis falls on flow between groups rather than advantage to the individual, and it should not be conflated with the strength of the tie itself, which is a separate question with its own page. The referent is a spanning connection across which things diffuse, described by the clusters it links rather than by the profit it earns.[5][4]

Unit

A tie that is the only route between two clusters

Recovery means

Not applicable

Measured by

Identified as bridges or shortcuts in a network, and by the flow of information or adoption across them