Research
On-device research index

arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,695 papers · 148 categories

Trend · papers per month

3827631,1451,526 · Jun 202019922001200920172026
48 results for random partition models

The study examines the balancedness of random partition models and finds the rich-get-richer characteristic is a result of model assumptions.

problem The balancedness of random partition models is largely neglected in the literature.
method Formulated a framework to define and study the balancedness of exchangeable random partition models, analyzed using product-form exchangeability and projectivity assumptions.
result The 'rich-get-richer' characteristic is an inevitable consequence of the model assumptions.

Many popular random partition models, such as the Chinese restaurant process and its two-parameter extension, fall in the class of exchangeable random partitions, and have found wide applicability in model-based clustering, population genetics, ecology or network analysis. While the exchangeability assumption is sensib…

2017-11-20abs ↗pdf ↗

Efficiently calculates PL model likelihood for partitioned preference data.

problem Computational infeasibility of calculating PL model likelihood for partitioned preference data.
method Random utility model formulation and efficient numerical integration approach.
result Proposed method outperforms existing LTR baselines and scales to real-world tasks.

We present a new way of constructing an ensemble classifier, named the Guided Random Forest (GRAF) in the sequel. GRAF extends the idea of building oblique decision trees with localized partitioning to obtain a global partitioning. We show that global partitioning bridges the gap between decision trees and boosting alg…

2019-09-02abs ↗pdf ↗

We consider the community detection problem in sparse random hypergraphs. Angelini et al. (2015) conjectured the existence of a sharp threshold on model parameters for community detection in sparse hypergraphs generated by a hypergraph stochastic block model. We solve the positive part of the conjecture for the case of…

2019-04-11abs ↗pdf ↗

Space partitioning methods such as random forests and the Mondrian process are powerful machine learning methods for multi-dimensional and relational data, and are based on recursively cutting a domain. The flexibility of these methods is often limited by the requirement that the cuts be axis aligned. The Ostomachion p…

2019-06-13abs ↗pdf ↗

Study exact partition recovery with same-cluster oracle, bounded error.

problem Exact recovery of partitions with same-cluster oracle in adversarial error.
method Novel connection to correlation clustering, Rényi-Ulam framework, upper and lower bounds, randomized algorithm analysis, adaptivity-query complexity study.
result Upper and lower bounds on worst-case query complexity, expected performance bounds of randomized algorithm.

Nonparametric regression for massive numbers of samples (n) and features (p) is an increasingly important problem. In big n settings, a common strategy is to partition the feature space, and then separately apply simple models to each partition set. We propose an alternative approach, which avoids such partitioning and…

2014-06-07abs ↗pdf ↗

ParK efficiently solves kernel ridge regression for large datasets.

problem Large-scale kernel ridge regression efficiency and accuracy.
method Partitioning feature space with random projections and iterative optimization.
result Provably maintains statistical accuracy with reduced space and time complexity.

Graph partitioning is the problem of dividing the nodes of a graph into balanced partitions while minimizing the edge cut across the partitions. Due to its combinatorial nature, many approximate solutions have been developed, including variants of multi-level methods and spectral clustering. We propose GAP, a Generaliz…

2019-03-02abs ↗pdf ↗

A new framework for clustering high-dimensional data using vertical shards.

problem Clustering high-dimensional data with the curse of dimensionality.
method Vertical Consensus Inference (VCI) that splits data into vertical shards for posterior inference.
result VCI can approximate inference on random partitions for high-dimensional data.

Partition Tree estimates conditional densities for mixed continuous and categorical variables.

problem Estimating conditional densities for mixed data types.
method Tree-based framework modeling conditional distributions as piecewise-constant densities on adaptive partitions, minimizing conditional negative log-likelihood.
result Improved probabilistic prediction compared to CART-style trees and state-of-the-art methods.

We learn the structure of a Markov Network between two groups of random variables from joint observations. Since modelling and learning the full MN structure may be hard, learning the links between two groups directly may be a preferable option. We introduce a novel concept called the \emph{partitioned ratio} whose fac…

2015-04-02abs ↗pdf ↗

Spectral algorithm recovers community structure in sparse hypergraphs.

problem Community detection in sparse random hypergraphs with community structure and higher-order interactions.
method Spectral algorithm with three steps: hyperedge selection, spectral partition, and correction/merging.
result Weak consistency achieved for weak signal-to-noise ratio.

The paper challenges the use of decision trees for pointwise inference due to slow convergence rates.

problem The slow convergence rates of decision trees in uniform norm, especially with non-vanishing probability.
method Demonstrates the limitations of adaptive recursive partitioning and shows how random forests can improve performance.
result Decision trees can fail to achieve polynomial rates of convergence in uniform norm, even with pruning.

Big data sets must be carefully partitioned into statistically similar data subsets that can be used as representative samples for big data analysis tasks. In this paper, we propose the random sample partition (RSP) data model to represent a big data set as a set of non-overlapping data subsets, called RSP data blocks,…

2017-12-12abs ↗pdf ↗

Randomization is minimax-optimal for variance in experimental design, even with structure.

problem Designing optimal randomized experiments for variance minimization.
method Analyzing permutation symmetric and non-symmetric sets of outcomes, proposing inference-constrained MSOD.
result Randomization is minimax-optimal for variance, even with structure, and requires uniformity constraints for Fisher's exact test.

New study shows limits of low-degree algorithms in finding large independent sets in sparse hypergraphs.

problem Finding large independent sets in sparse random hypergraphs.
method Low-degree polynomial algorithms are analyzed to determine their limits.
result Low-degree algorithms can find independent sets of density up to \(\left(\frac{\log d}{(r-1)d} ight)^{1/(r-1)}\), but no larger.

New bound on partition function proves Kähler-Einstein stability.

problem Proving Kähler-Einstein metrics on complex manifolds.
method Quantitative bound on partition function, connecting probabilistic and quantization approaches.
result Direct analytic proof of Kähler-Einstein stability for uniformly Gibbs stable manifolds.

FDSKL algorithm trains vertically partitioned data with kernels securely and efficiently.

problem Training vertically partitioned data with kernels while maintaining privacy.
method FDSKL algorithm using random features and doubly stochastic gradients for federated learning.
result FDSKL achieves sublinear convergence and guarantees data security.

Min-cut clustering, based on minimizing one of two heuristic cost-functions proposed by Shi and Malik, has spawned tremendous research, both analytic and algorithmic, in the graph partitioning and image segmentation communities over the last decade. It is however unclear if these heuristics can be derived from a more g…

2008-11-26abs ↗pdf ↗

flexBART improves BART for categorical predictors by creating flexible tree partitions.

problem Limitation of BART in handling categorical predictors with one-hot encoding.
method flexBART re-implements BART with regression trees that can assign multiple levels to both branches of a decision tree node, and proposes a new decision rule prior for spatial data.
result flexBART often yields improved predictive performance and scales better to larger datasets than existing BART implementations.

Spectral clustering is a celebrated algorithm that partitions objects based on pairwise similarity information. While this approach has been successfully applied to a variety of domains, it comes with limitations. The reason is that there are many other applications in which only \emph{multi}-way similarity measures ar…

2018-05-23abs ↗pdf ↗

The modern scale of data has brought new challenges to Bayesian inference. In particular, conventional MCMC algorithms are computationally very expensive for large data sets. A promising approach to solve this problem is embarrassingly parallel MCMC (EP-MCMC), which first partitions the data into multiple subsets and r…

2015-06-10abs ↗pdf ↗

Graphs approximate semigroups for diffusion on Riemannian manifolds.

problem Approximating semigroups for diffusion on Riemannian manifolds.
method Discretized approximation using random walks on proximity graphs.
result Quantitative error estimates for convergence of discrete semigroups to continuous semigroups.

We propose a multiresolution Gaussian process to capture long-range, non-Markovian dependencies while allowing for abrupt changes. The multiresolution GP hierarchically couples a collection of smooth GPs, each defined over an element of a random nested partition. Long-range dependencies are captured by the top-level GP…

2012-09-05abs ↗pdf ↗

This research designs a data-driven partition to test independence between continuous variables.

problem Testing independence between continuous random variables.
method Empirical log-likelihood statistic and data-driven tree-structured partition.
result Strongly consistent test of independence over probability families.

We consider a random link, which is defined as the closure of a braid obtained from a random walk on the braid group. For such a random link, the expected value for the number of components was calculated by Jiming Ma. In this paper, we determine the most expected number of components for a random link, and further, co…

2015-07-11abs ↗pdf ↗

Undirected graphical models encode in a graph GG the dependency structure of a random vector YY. In many applications, it is of interest to model YY given another random vector XX as input. We refer to the problem of estimating the graph G(x)G(x) of YY conditioned on X=xX=x as ``graph-valued regression.'' In this pap…

2010-06-21abs ↗pdf ↗