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Pivotal CLTs for Pseudolikelihood via Conditional Centering in Dependent Random Fields

Nabarun Deb

TL;DR

This work develops a general limit theory for conditionally centered statistics in dependent random fields, showing that under verifiable smoothness of conditional means, the centered statistic converges to a Gaussian scale mixture with a random scale driven by a quadratic-variance term and interaction effects. A data-driven studentization yields a pivotal Gaussian limit, enabling robust, non-sparse MPLE-based inference for models with dense and irregular dependencies. The framework yields new CLTs for MPLEs in Ising models (including tensor interactions) and ERGMs, including joint CLTs for inverse temperature and magnetization in dense regimes and beyond sub-criticality. The approach unifies analysis across dense graphs and irregular graphon limits, providing practical tools for inference on modern network models while using a novel method of moments with combinatorial decision-tree pruning. Overall, the results offer a versatile, exact asymptotic regime for pseudolikelihood-based inference in complex dependent structures with broad applicability in statistical physics and network modeling.

Abstract

In this paper, we study fluctuations of conditionally centered statistics of the form $$N^{-1/2}\sum_{i=1}^N c_i(g(σ_i)-\mathbb{E}_N[g(σ_i)|σ_j,j\neq i])$$ where $(σ_1,\ldots ,σ_N)$ are sampled from a dependent random field, and $g$ is some bounded function. Our first main result shows that under weak smoothness assumptions on the conditional means (which cover both sparse and dense interactions), the above statistic converges to a Gaussian \emph{scale mixture} with a random scale determined by a \emph{quadratic variance} and an \emph{interaction component}. We also show that under appropriate studentization, the limit becomes a pivotal Gaussian. We leverage this theory to develop a general asymptotic framework for maximum pseudolikelihood (MPLE) inference in dependent random fields. We apply our results to Ising models with pairwise as well as higher-order interactions and exponential random graph models (ERGMs). In particular, we obtain a joint central limit theorem for the inverse temperature and magnetization parameters via the joint MPLE (to our knowledge, the first such result in dense, irregular regimes), and we derive conditionally centered edge CLTs and marginal MPLE CLTs for ERGMs without restricting to the ``sub-critical" region. Our proof is based on a method of moments approach via combinatorial decision-tree pruning, which may be of independent interest.

Pivotal CLTs for Pseudolikelihood via Conditional Centering in Dependent Random Fields

TL;DR

This work develops a general limit theory for conditionally centered statistics in dependent random fields, showing that under verifiable smoothness of conditional means, the centered statistic converges to a Gaussian scale mixture with a random scale driven by a quadratic-variance term and interaction effects. A data-driven studentization yields a pivotal Gaussian limit, enabling robust, non-sparse MPLE-based inference for models with dense and irregular dependencies. The framework yields new CLTs for MPLEs in Ising models (including tensor interactions) and ERGMs, including joint CLTs for inverse temperature and magnetization in dense regimes and beyond sub-criticality. The approach unifies analysis across dense graphs and irregular graphon limits, providing practical tools for inference on modern network models while using a novel method of moments with combinatorial decision-tree pruning. Overall, the results offer a versatile, exact asymptotic regime for pseudolikelihood-based inference in complex dependent structures with broad applicability in statistical physics and network modeling.

Abstract

In this paper, we study fluctuations of conditionally centered statistics of the form where are sampled from a dependent random field, and is some bounded function. Our first main result shows that under weak smoothness assumptions on the conditional means (which cover both sparse and dense interactions), the above statistic converges to a Gaussian \emph{scale mixture} with a random scale determined by a \emph{quadratic variance} and an \emph{interaction component}. We also show that under appropriate studentization, the limit becomes a pivotal Gaussian. We leverage this theory to develop a general asymptotic framework for maximum pseudolikelihood (MPLE) inference in dependent random fields. We apply our results to Ising models with pairwise as well as higher-order interactions and exponential random graph models (ERGMs). In particular, we obtain a joint central limit theorem for the inverse temperature and magnetization parameters via the joint MPLE (to our knowledge, the first such result in dense, irregular regimes), and we derive conditionally centered edge CLTs and marginal MPLE CLTs for ERGMs without restricting to the ``sub-critical" region. Our proof is based on a method of moments approach via combinatorial decision-tree pruning, which may be of independent interest.

Paper Structure

This paper contains 36 sections, 31 theorems, 354 equations, 1 figure, 2 algorithms.

Key Result

Theorem 2.1

Suppose Assumptions as:coeff and as:cmean hold. Define the random variables We assume that there exists $\eta>0$ such that Then given any sequence of positive reals $\{a_N\}_{N\ge 1}$ such that $a_N\to 0$, we have

Figures (1)

  • Figure 1: In the above diagram, we plot the complete decision tree according to \ref{['alg:construct_tree']} when $p=1$, $q=2$. The root node is in yellow, the leaf nodes are in red (except in one case where it is in cyan, the reasons for which are explained in the main text) and the non leaf nodes are in green. The values of $\mathcal{D},\mathcal{E}$, and $M$ are specified along with each node (we drop the subscripts used in Algorithm \ref{['alg:construct_tree']}-\ref{['alg:construct_treep2']} to avoid notational clutter). At the root, $M=j_2$, $\mathcal{D}=\{i_1\}$, $\mathcal{E}=\{j_1,j_2\}$ (see step 3 of \ref{['alg:construct_tree']}). Therefore, in the first generation, $\mathcal{D}\subseteq \{i_1\}$ and $\mathcal{E}\subseteq \{j_1\}$. By \ref{['prop:baseprop']}, the case $(\mathcal{D},\mathcal{E})=(\{i_1\},\{j_1\})$ does not contribute. This leads to $3$ choices for $(\mathcal{D},\mathcal{E})$ which form the $3$ nodes of the first generation. In $2$ of these nodes $\mathcal{E}=\phi$, and consequently their child nodes will have $\mathcal{E}=\phi$ and $M=-\infty$ (see \ref{['eq:gen2pt2b']}) which satisfy the termination condition from step 17 in \ref{['alg:construct_treep2']}. For the other node in the first generation, the only remaining option is $\mathcal{D}=\phi$, $\mathcal{E}=\{j_1\}$. For its child nodes, by step 8 of \ref{['alg:construct_tree']} (see \ref{['eq:gen2pt2a']}), the only options of $\mathcal{E}$ are $\phi$ and $\{j_1\}$. The case $\mathcal{E}=\phi$ once again satisfies the termination condition from step 17 of \ref{['alg:construct_treep2']} and is thus a leaf node. Therefore the only node in the second generation which has child nodes is the case where $\mathcal{D}=\phi$, $\mathcal{E}=\{j_1\}$. This in turn implies $M=\{j_1\}$ (see \ref{['eq:gen2pt2b']}). The third and fourth generations are formed similarly using the recursive approach described in \ref{['alg:construct_treep2']}.

Theorems & Definitions (78)

  • Theorem 2.1
  • Theorem 2.2
  • Remark 2.1: Avoiding \ref{['as:empcon']}
  • Remark 2.2: Comparison with Comets1998
  • Proposition 3.1: CLT for MPLE
  • Proposition 3.2: Consistency of MPLE
  • Theorem 4.1
  • Remark 4.1: Broader implications
  • Theorem 5.1
  • Definition 5.1: Parameter space
  • ...and 68 more