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Government promises 50,000 new apprenticeships in youth employment push

BBC News

The government says some 50,000 young people are expected to benefit from a programme to expand apprenticeships as it looks to tackle youth unemployment. The £725 million package, which was earmarked in the Budget and covers the next three years, will be used to create apprenticeships in sectors including AI, hospitality and engineering. Apprenticeships for people under the age of 25 at small and medium-sized businesses will be fully funded as part of the package, removing the 5% that they currently have to pay. The government is aiming to reverse a decline in the number of young people starting apprenticeships, which has fallen by almost 40% in the past decade. The funding also includes £140m for a pilot that the Department for Work and Pensions says will allow local mayors to connect young people with employers and apprenticeship opportunities, although it is unclear exactly how the money will be used.


Nested replicator dynamics, nested logit choice, and similarity-based learning

Mertikopoulos, Panayotis, Sandholm, William H.

arXiv.org Artificial Intelligence

We consider a model of learning and evolution in games whose action sets are endowed with a partition-based similarity structure intended to capture exogenous similarities between strategies. In this model, revising agents have a higher probability of comparing their current strategy with other strategies that they deem similar, and they switch to the observed strategy with probability proportional to its payoff excess. Because of this implicit bias toward similar strategies, the resulting dynamics - which we call the nested replicator dynamics - do not satisfy any of the standard monotonicity postulates for imitative game dynamics; nonetheless, we show that they retain the main long-run rationality properties of the replicator dynamics, albeit at quantitatively different rates. We also show that the induced dynamics can be viewed as a stimulus-response model in the spirit of Erev & Roth (1998), with choice probabilities given by the nested logit choice rule of Ben-Akiva (1973) and McFadden (1978). This result generalizes an existing relation between the replicator dynamics and the exponential weights algorithm in online learning, and provides an additional layer of interpretation to our analysis and results.


Convex Latent Effect Logit Model via Sparse and Low-rank Decomposition

Zhan, Hongyuan, Madduri, Kamesh, Shankar, Venkataraman

arXiv.org Machine Learning

In this paper, we propose a convex formulation for learning logistic regression model (logit) with latent heterogeneous effect on sub-population. In transportation, logistic regression and its variants are often interpreted as discrete choice models under utility theory (McFadden, 2001). Two prominent applications of logit models in the transportation domain are traffic accident analysis and choice modeling. In these applications, researchers often want to understand and capture the individual variation under the same accident or choice scenario. The mixed effect logistic regression (mixed logit) is a popular model employed by transportation researchers. To estimate the distribution of mixed logit parameters, a non-convex optimization problem with nested high-dimensional integrals needs to be solved. Simulation-based optimization is typically applied to solve the mixed logit parameter estimation problem. Despite its popularity, the mixed logit approach for learning individual heterogeneity has several downsides. First, the parametric form of the distribution requires domain knowledge and assumptions imposed by users, although this issue can be addressed to some extent by using a non-parametric approach. Second, the optimization problems arise from parameter estimation for mixed logit and the non-parametric extensions are non-convex, which leads to unstable model interpretation. Third, the simulation size in simulation-assisted estimation lacks finite-sample theoretical guarantees and is chosen somewhat arbitrarily in practice. To address these issues, we are motivated to develop a formulation that models the latent individual heterogeneity while preserving convexity, and avoids the need for simulation-based approximation. Our setup is based on decomposing the parameters into a sparse homogeneous component in the population and low-rank heterogeneous parts for each individual.


A Small College Hopes to Claim Artificial Intelligence for the Liberal Arts - EdSurge News

#artificialintelligence

Colby College is carving out space in the liberal arts canon for artificial intelligence. Thanks to a $30 million gift from an alumnus, the small, selective college in Maine is establishing the Davis Institute for Artificial Intelligence, which aims to integrate machine learning, natural language processing and big data into instruction and research across the college. "We want to be sure we're preparing students well for their futures: lives and careers of meaning and purpose," says Margaret McFadden, provost and dean of faculty at Colby. "Well-educated people have to understand AI, what these tools are and how to use them." Artificial intelligence has homes at other U.S. higher ed institutions, including Massachusetts Institute of Technology, the University of Georgia, Stevens Institute of Technology in New Jersey, and Stanford University.


Human consciousness is actually the brain's 'energy field', claims scientist

Daily Mail - Science & tech

A professor of neuroscience at the University of Surrey claims to have solved the long-standing mystery of what creates human consciousness. According to Dr Johnjoe McFadden, the electromagnetic field produced by the brain's neurons is what produces this uniquely human trait. Vast amounts of research has gone into deciphering why we have the ability to know we think, whereas other animals do not. Previous attempts to understand this have included the spiritual and supernatural, including suggesting it comes from a soul. But Professor McFadden is basing his theory, published in the journal Neuroscience of Consciousness, on well-known scientific fact.


A Coefficient of Determination for Probabilistic Topic Models

Jones, Tommy

arXiv.org Machine Learning

--This research proposes a new (old) metric for evaluating goodness of fit in topic models, the coefficient of determination, or R 2 . Within the context of topic modeling, R 2 has the same interpretation that it does when used in a broader class of statistical models. Reporting R 2 with topic models addresses two current problems in topic modeling: a lack of standard cross-contextual evaluation metrics for topic modeling and ease of communication with lay audiences. The author proposes that R 2 should be reported as a standard metric when constructing topic models. I NTRODUCTION According to an often-quoted but never cited definition, "the goodness of fit of a statistical model describes how well it fits a set of observations. Measures of goodness of fit typically summarize the discrepancy between observed values and the values expected under the model in question." 1 Goodness of fit measures vary with the goals of those constructing the statistical model. Inferential goals may emphasize in-sample fit while predictive goals may emphasize out-of-sample fit. Prior information may be included in the goodness of fit measure for Bayesian models, or it may not. Goodness of fit measures may include methods to correct for model overfitting. In short, goodness of fit measures the performance of a statistical model against the ground truth of observed data. Fitting the data well is generally a necessary--though not sufficient--condition for trust in a statistical model, whatever its goals. Of course, goodness of fit is only one concern in statistical modeling.


Conjoint Analysis: A Primer

@machinelearnbot

Say, you're developing a new product. One thing you'll want to know is how important various features of a product or service of that type are to consumers. We often try to get at this by asking respondents directly in focus groups or quantitative surveys, but this may mislead us because many people have difficulty answering questions such as these. In surveys, for example, many will claim that just about everything about a product is important. Instead, what conjoint does is force respondents to make trade-offs.


Analysis of the Web User Behavior with a Psychologically-Based Diffusion Model

Roman, Pablo Enrique (University of Chile) | Velasquez, Juan Domingo (University of Chile)

AAAI Conferences

This work presents a new application of a mathematical theory of psychological behavior from Usher and McClelland and the random utility model from McFadden, to the web user behavior. The model describes the stochastic behavior of a general kind of web users, consisting of the probability of following a hyperlink for a specific length of time. The simulation experiment together with the artificial agent illustrates behavioral patterns characteristic of human subjects.