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Arabin Kumar Dey

Publications and source records attributed to Arabin Kumar Dey.

15 recordsLinked to original sources
arXiv2024

Some variation of COBRA in sequential learning setup

This research paper introduces innovative approaches for multivariate time series forecasting based on different variations of the combined regression strategy. We use specific data preprocessing techniques which makes a radical change in the behaviour of prediction. We compare the performance of the model based on two types of hyper-parameter tuning Bayesian optimisation (BO) and Usual Grid search. Our proposed methodologies outperform all state-of-the-art comparative models. We illustrate the methodologies through eight time series datasets from three categories: cryptocurrency, stock index, and short-term load forecasting.

stat.ML↗
arXiv2023

An EM algorithm for absolutely continuous Marshall-Olkin bivariate Pareto distribution with location and scale

In this paper, we have considered a Block-Basu type bivariate Pareto distribution. Here in the standard manner, first Marshall-Olkin type singular bivariate distribution has been constructed, and then by taking away the singular component similar to the Block and Basu model, an absolute continuous BB-BVPA model has been constructed. Further, the location and scale parameters also have been introduced. Therefore, the model has seven parameters. Different properties of this absolutely continuous distribution are derived. Since the maximum likelihood estimators of the parameters cannot be expressed in a closed form, we propose to use an EM algorithm to compute the estimators of the model parameters. Some simulation experiments have been performed for illustrative purposes. The model is fitted to rainfall data in the context of landslide risk estimation.

stat.CO↗
arXiv2022

Confidence Interval Construction for Multivariate time series using Long Short Term Memory Network

In this paper we propose a novel procedure to construct a confidence interval for multivariate time series predictions using long short term memory network. The construction uses a few novel block bootstrap techniques. We also propose an innovative block length selection procedure for each of these schemes. Two novel benchmarks help us to compare the construction of this confidence intervals by different bootstrap techniques. We illustrate the whole construction through S\&P $500$ and Dow Jones Index datasets.

stat.ME↗
arXiv2022

Integrated Brier Score based Survival Cobra -- A regression based approach

Recently Goswami et al. \cite{goswami2022concordance} introduced two novel implementations of combined regression strategy to find the conditional survival function. The paper uses regression-based weak learners and provides an alternative version of the combined regression strategy (COBRA) ensemble using the Integrated Brier Score to predict conditional survival function. We create a novel predictor based on a weighted version of all machine predictions taking weights as a specific function of normalized Integrated Brier Score. We use two different norms (Frobenius and Sup norm) to extract the proximity points in the algorithm. Our implementations consider right-censored data too. We illustrate the proposed algorithms through some real-life data analysis.

cs.LG↗
arXiv2022

Concordance based Survival Cobra with regression type weak learners

In this paper, we predict conditional survival functions through a combined regression strategy. We take weak learners as different random survival trees. We propose to maximize concordance in the right-censored set up to find the optimal parameters. We explore two approaches, a usual survival cobra and a novel weighted predictor based on the concordance index. Our proposed formulations use two different norms, say, Max-norm and Frobenius norm, to find a proximity set of predictions from query points in the test dataset. We illustrate our algorithms through three different real-life dataset implementations.

stat.ML↗
arXiv2020

Construction of confidence interval for a univariate stock price signal predicted through Long Short Term Memory Network

In this paper, we show an innovative way to construct bootstrap confidence interval of a signal estimated based on a univariate LSTM model. We take three different types of bootstrap methods for dependent set up. We prescribe some useful suggestions to select the optimal block length while performing the bootstrapping of the sample. We also propose a benchmark to compare the confidence interval measured through different bootstrap strategies. We illustrate the experimental results through some stock price data set.

stat.ML↗
arXiv2018

Parameter Estimation of absolute continuous four parameter Geometric Marshall-Olkin bivariate Pareto Distribution

In this paper we formulate a four parameter absolute continuous Geometric Marshall-Olkin bivariate Pareto distribution and study its parameter estimation through EM algorithm and also explore the bayesian analysis through slice cum Gibbs sampler approach. Numerical results are shown to verify the performance of the algorithms. We illustrate the procedures through a real life data analysis.

stat.ME↗
arXiv2018

Bayesian analysis of absolute continuous Marshall-Olkin bivariate Pareto distribution with location and scale parameters

This paper provides two different novel approaches of slice sampling to estimate the parameters of absolute continuous Marshall-Olkin bivariate Pareto distribution with location and scale parameters. We carry out the bayesian analysis taking gamma prior for shape and scale parameters and truncated normal for location parameters. Credible intervals and coverage probabilities are also provided for all methods. A real-life data analysis is shown for illustrative purpose.

stat.ME↗
arXiv2018

A novel Empirical Bayes with Reversible Jump Markov Chain in User-Movie Recommendation system

In this article we select the unknown dimension of the feature by re- versible jump MCMC inside a simulated annealing in bayesian set up of collaborative filter. We implement the same in MovieLens small dataset. We also tune the hyper parameter by using a modified empirical bayes. It can also be used to guess an initial choice for hyper-parameters in grid search procedure even for the datasets where MCMC oscillates around the true value or takes long time to converge.

stat.ML↗
arXiv2018

Some variations on Ensembled Random Survival Forest with application to Cancer Research

In this paper we describe a novel implementation of adaboost for prediction of survival function. We take different variations of the algorithm and compare the algorithms based on system run time and root mean square error. Our construction includes right censoring data and competing risk data too. We take different data set to illustrate the performance of the algorithms.

stat.ME↗
arXiv2018

Hierarchical EM algorithm for estimating the parameters of Mixture of Bivariate Generalized Exponential distributions

This paper provides a mixture modeling framework using the bivariate generalized exponential distribution. We study different properties of this mixture distribution. Hierarchical EM algorithm is developed for finding the estimates of the parameters. The algorithm takes very large sample size to work as it contains many stages of approximation. Numerical Results are provided for more illustration.

stat.CO↗
arXiv2017

Bayesian analysis of three parameter singular Marshall-Olkin bivariate Pareto distribution

This paper provides bayesian analysis of singular Marshall-Olkin bivariate Pareto distribution. We consider three parameter singular Marshall-Olkin bivariate Pareto distribution. We consider two types of prior - reference prior and gamma prior. Bayes estimate of the parameters are calculated based on slice cum gibbs sampler and Lindley approximation. Credible interval is also provided for all methods and all prior distributions. A data analysis is kept for illustrative purpose.

stat.ME↗
arXiv2017

A case study of Empirical Bayes in User-Movie Recommendation system

In this article we provide a formulation of empirical bayes described by Atchade (2011) to tune the hyperparameters of priors used in bayesian set up of collaborative filter. We implement the same in MovieLens small dataset. We see that it can be used to get a good initial choice for the parameters. It can also be used to guess an initial choice for hyper-parameters in grid search procedure even for the datasets where MCMC oscillates around the true value or takes long time to converge.

stat.ML↗
arXiv2016

Bayesian Analysis of Modified Weibull distribution under progressively censored competing risk model

In this paper we study bayesian analysis of Modified Weibull distribution under progressively censored competing risk model. This study is made for progressively censored data. We use deterministic scan Gibbs sampling combined with slice sampling to generate from the posterior distribution. Posterior distribution is formed by taking prior distribution as reference prior. A real life data analysis is shown for illustrative purpose.

stat.CO↗