Calculates goodness of fit statistics for relational data matrices, evaluating second-order (dyadic) and third-order (triadic) dependence patterns. These statistics are useful for assessing model fit in network analysis and relational data modeling.
Value
A named numeric vector containing five goodness-of-fit statistics:
- sd.rowmean
Standard deviation of row means. Measures the heterogeneity in out-degree centrality (sender effects). Higher values indicate more variation in how active nodes are as senders.
- sd.colmean
Standard deviation of column means. Measures the heterogeneity in in-degree centrality (receiver effects). Higher values indicate more variation in how popular nodes are as receivers.
- dyad.dep
Dyadic dependence/reciprocity correlation. Pearson correlation between Y\[i,j\] and Y\[j,i\] across all dyads. Positive values indicate reciprocity (mutual relationships), negative values indicate anti-reciprocity. Range: \[-1, 1\].
- cycle.dep
Cyclic/transitive triadic dependence. Normalized sum of products along three-cycles (i to j to k to i). Positive values indicate transitivity clustering, where 'a friend of a friend is a friend'. Based on the trace of the cubed centered matrix, normalized by the trace of the cubed data availability matrix and the cubed standard deviation.
- trans.dep
Transitive triadic dependence. Normalized sum of products along two-paths that close into triangles (i to j to k with k to i). Measures the tendency for open triads to close. Based on the trace of the product E*E'*E where E is the centered matrix, normalized appropriately.
Details
The function computes network statistics that capture different aspects of network structure beyond simple density. These statistics are particularly useful for:
Model checking: comparing observed statistics to those from simulated networks
Model selection: choosing between models that better capture network dependencies
Descriptive analysis: summarizing key structural features of the network
Missing values in Y are handled by pairwise deletion for correlations and are excluded from matrix products in triadic calculations.
Examples
data(YX_nrm)
gof_stats(YX_nrm$Y)
#> sd.rowmean sd.colmean dyad.dep cycle.dep trans.dep
#> 0.92646818 0.27555881 0.66792884 0.06139376 0.07380099