In recent years, diffusion models have emerged as powerful tools for generating ensemble members in meteorology. In this work, we demonstrate that a Denoising Diffusion Implicit Model (DDIM) can effectively control ensemble variance by varying the number of diffusion steps. Introducing a theoretical framework, we relate diffusion steps to the variance expressed by the reverse diffusion process. Focusing on reanalysis downscaling, we propose an ensemble diffusion model for the full ERA5-to-CERRA domain, generating variance-calibrated ensemble members for wind speed at full spatial and temporal resolution. Our method aligns global mean variance with a reference ensemble dataset and ensures spatial variance is distributed in accordance with observed meteorological variability. Additionally, we address the lack of ensemble information in the CARRA dataset, showcasing the utility of our approach for efficient, high-resolution ensemble generation.

There have been significant efforts devoted to solving the longevity risk given that a continuous growth in population ageing has become a severe issue for many developed countries over the past few decades. The Cairns-Blake-Dowd (CBD) model, which incorporates cohort effects parameters in its parsimonious design, is one of the most well-known approaches for mortality modelling at higher ages and longevity risk. This article proposes a novel mixed-effects time-series approach for mortality modelling and forecasting with considerations of age groups dependence and random cohort effects parameters. The proposed model can disclose more mortality data information and provide a natural quantification of the model parameters uncertainties with no pre-specified constraint required for estimating the cohort effects parameters. The abilities of the proposed approach are demonstrated through two applications with empirical male and female mortality data. The proposed approach shows remarkable improvements in terms of forecast accuracy compared to the CBD model in the short-, mid-and long-term forecasting using mortality data of several developed countries in the numerical examples.

There has been an increasing demand for demographic modelling and forecasting over the last few decades, driven by many developed countries are now suffering a rapid decline in mortality and fertility, leading to a significant increase in expenditures on health services for an ageing population and a shortage of future labour. A better understanding of the mortality and fertility patterns and trends is always of importance for all stakeholders in a society as the mortality forecasts, for example, play a vital role for the insurance and pensions industries in pricing their insurance products. The fertility predictions are also of great interest to the government and education sectors in planing children's welfare and educational services. Unlike the biological and the medical methods, statisticians have developed very different and purely mathematical methods to model the demographic patterns and trends which are well-documented by Preston et al. (2000). The history of demographic modelling with the mathematical approaches can be traced back to some deterministic models proposed in the midnineteenth century, see, for example, Gompertz (1825) and Makeham (1860). The deterministic models are, however, restricted with few fixed factors and have no stochastic process considered owing to the lack of computing capability in that early period.

Human mortality patterns and trajectories in closely related populations are likely linked together and share similarities. It is always desirable to model them simultaneously while taking their heterogeneity into account. This paper introduces two new models for joint mortality modelling and forecasting multiple subpopulations in adaptations of the multivariate functional principal component analysis techniques. The first model extends the independent functional data model to a multi-population modelling setting. In the second one, we propose a novel multivariate functional principal component method for coherent modelling. Its design primarily fulfils the idea that when several subpopulation groups have similar socio-economic conditions or common biological characteristics, such close connections are expected to evolve in a non-diverging fashion. We demonstrate the proposed methods by using sex-specific mortality data. Their forecast performances are further compared with several existing models, including the independent functional data model and the Product-Ratio model, through comparisons with mortality data of ten developed countries. Our experiment results show that the first proposed model maintains a comparable forecast ability with the existing methods. In contrast, the second proposed model outperforms the first model as well as the current models in terms of forecast accuracy, in addition to several desirable properties.

The year 2016 proved to be an important milestone in the history of Artificial Intelligence (AI). Though the researchers have been working on creating intelligent machines for long, the year 2016 witnessed the concept leaving the realm of science-fiction to become more tangible and realistic. The year began with the Facebook founder Mark Zuckerberg announcing his plans to build an artificial assistant for his home. As the year proceeded, organisations across the globe started increasingly investing their resources towards the research and development of AI. As the word caught on pace, tech titans including Google, Intel and Apple raced to acquire private companies working to advance artificial intelligence.

Well, 2016 has been a heck of a year – so we're going to see it out in the best way possible: with a candid discussion about the best, worst and most interesting moments from the world of video games. On 15 December, the Guardian games section is holding its annual review of the year event at our London headquarters. Joining games editor Keith Stuart on stage will be Tomb Raider writer Rhianna Pratchett, comedian and broadcaster Ellie Gibson (from hit Dave show, Dara O Briain's Go 8 Bit), and designer and academic Phoenix Perry, as well as Alice Bell from games site VideoGamer and Guardian games contributors Simon Parkin and Jordan Erica Webber. We'll be looking at the lows and highs of the year, from the majestic Uncharted 4 to the now available Final Fantasy XV; from the promise of virtual reality to the ... unfulfilled promise of virtual reality; from the biggest commercial releases to the strangest, most beautiful little indie gems. We'll also be asking: what do the games of 2016 tell us about what we can expect in 2017 and beyond?

"The Silicon Review 50 Smartest Companies of the Year 2016 program identifies the companies transforming the way we work via cutting-edge technology. These companies are leading the seismic shifts that today's company leaders need to be thinking about before it's too late. We selected WorkCompass because of its unique application of artificial intelligence to improve performance appraisal, its revenue growth, customer reviews and domain influence," said Manish Pandey, Editor-in-Chief of The Silicon Review Magazine. "We are honored to be recognized by The Silicon Review Magazine as the one of the 50 Smartest Companies of the Year 2016," said Denis Coleman, Founder and CEO at WorkCompass. "In 2012, I left my job to found WorkCompass. I wanted to transform performance appraisal into an ongoing process about coaching and mentoring staff to achieve their full potential. I'm incredibly proud of what we have achieved so far at WorkCompass".