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Sunbelt XXXI International Network for Social Network ... - INSNA

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Measurement Error In <strong>Network</strong> Analysis: The Effects Of Missing, Spurious, And Aggregated DataWang, Dan J.; Shi, Xiaolin; McFarland, Daniel A.; Leskovec, JureAnalyzing <strong>Network</strong> Data / BlockmodelingMethods, Centrality, Missing DataSAT.AM2We embed missing data in a broader classification of measurement error scenarios. In addition to missing data, which we term "false negative nodes andedges", we analyze the consequences of "false positive nodes and edges", and "falsely aggregated and disaggregated nodes". We simulate these sixmeasurement errors in an online social network and a publication citation network, reporting their effects on four node‐level measures‐‐degree centrality,clustering coefficient, network constraint, and eigenvector centrality. Our results suggest that in networks with more positively‐skewed degree distributionsand higher average clustering, these measures tend to be less resistant to most <strong>for</strong>ms of measurement error. In addition, we argue that the sensitivity of agiven measure to an error scenario depends on the nature of the measure's calculation. Thus, we revise the claim that the more `global' a measure, the lessresistant it is to measurement error. We find that clustering coefficient and network constraint are, in general, the least resistant of our four measures eventhough they are less `global' measures than eigenvector centrality. Finally, we anchor our discussion to examples of past network research that likely sufferfrom these different <strong>for</strong>ms of measurement error while making recommendations <strong>for</strong> error correction strategies.Meeting In Settings, Mating In <strong>Network</strong>s: Stochastic Actor‐oriented Models For Large <strong>Network</strong> DynamicsPreciado, Paulina; Snijders, Tom A.; Lospinoso, Joshua A.<strong>Network</strong> DynamicsIncomplete in<strong>for</strong>mation, Settings, Meeting and mating, Stochastic Actor‐ Oriented Models, Large network dynamicsTHURS.PM1Stochastic Actor‐Oriented Models (SAOM; Snijders, 2001), provide a flexible and rich framework <strong>for</strong> analysing social network dynamics. These models assumethat actors have full in<strong>for</strong>mation about the network and about the other actors. For large networks the assumption of full in<strong>for</strong>mation is often not realistic. Inthis paper we extend the SAOM by proposing that social actors are embedded in settings (Feld, 1981; Pattison & Robins, 2002) in which they have differentlevels of in<strong>for</strong>mation about the network and the other actors. In their primary setting, which includes their direct network neighbourhood, actors have fullin<strong>for</strong>mation about the other actors and the ties between them, and the usual SAOM specification operates. Besides, actors can have meeting settings in whicha two‐step process takes place: at a given moment, a particular actor i randomly meets another actor j (“meeting”), and acquires in<strong>for</strong>mation thatprobabilistically determines the creation of a tie (mating). Examples of meeting settings are institutions (schools, work places), neighbourhoods and theresidual category of the rest of the network. We compare the standard SAOM, with the extended settings specification using a three‐wave friendship networkof all adolescents in an age cohort living in a small Swedish town. Computing time <strong>for</strong> large networks is reduced by the new modelling framework.

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