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More UAE students take up technology, coding courses

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… from coding to artificial intelligence, machine learning and deep learning, said Dr Raja M, head of the campus’ Department of Computer Science.


Likelihood estimation of sparse topic distributions in topic models and its applications to Wasserstein document distance calculations

arXiv.org Machine Learning

This paper studies the estimation of high-dimensional, discrete, possibly sparse, mixture models in topic models. The data consists of observed multinomial counts of $p$ words across $n$ independent documents. In topic models, the $p\times n$ expected word frequency matrix is assumed to be factorized as a $p\times K$ word-topic matrix $A$ and a $K\times n$ topic-document matrix $T$. Since columns of both matrices represent conditional probabilities belonging to probability simplices, columns of $A$ are viewed as $p$-dimensional mixture components that are common to all documents while columns of $T$ are viewed as the $K$-dimensional mixture weights that are document specific and are allowed to be sparse. The main interest is to provide sharp, finite sample, $\ell_1$-norm convergence rates for estimators of the mixture weights $T$ when $A$ is either known or unknown. For known $A$, we suggest MLE estimation of $T$. Our non-standard analysis of the MLE not only establishes its $\ell_1$ convergence rate, but reveals a remarkable property: the MLE, with no extra regularization, can be exactly sparse and contain the true zero pattern of $T$. We further show that the MLE is both minimax optimal and adaptive to the unknown sparsity in a large class of sparse topic distributions. When $A$ is unknown, we estimate $T$ by optimizing the likelihood function corresponding to a plug in, generic, estimator $\hat{A}$ of $A$. For any estimator $\hat{A}$ that satisfies carefully detailed conditions for proximity to $A$, the resulting estimator of $T$ is shown to retain the properties established for the MLE. The ambient dimensions $K$ and $p$ are allowed to grow with the sample sizes. Our application is to the estimation of 1-Wasserstein distances between document generating distributions. We propose, estimate and analyze new 1-Wasserstein distances between two probabilistic document representations.


Voice cloning of growing interest to actors and cybercriminals

BBC News

Voice cloning can also be used to translate an actor's words into different languages, thereby potentially meaning, for example, that US film production companies will no longer need to hire additional actors to make dubbed versions of their movies for overseas distribution.


FSC Korea Issues Guidelines on AI-based Financial Services

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The guidelines emphasise the need to firms to manage the source and quality of data used in machine learning, establish a privacy protection system …


Training centers to bridge digital gap for elderly

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Officials jointly launch the first batch of Digital Training Bases for Seniors at the World Artificial Intelligence Conference 2021 on Saturday.


Countering security concerns posed by latest AI technologies

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These standards cover areas such as synthetic audio and video based on artificial intelligence, machine learning algorithm security, and artificial …


Recycling app uses AI to identify rubbish

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A new recycling app will use artificial intelligence to help Australians work out if their rubbish can be recycled.


Artificial Intelligence (AI) in Construction Market SWOT Analysis by Size, Status and Forecast …

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Latest published market study on Global Artificial Intelligence (AI) in Construction Market provides an overview of the current market dynamics in the …



Soldex – The Solana Based Decentralized Exchange Introduces AI Trading

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Notably, the Soldex trading platform will have machine learning algorithms and a team of data sciences and experts.