An account is given of a variety of linear filters which can be used for extracting trends from economic time series and for generating de-trended series. A family of rational square-wave filters is described which enable designated frequency ranges to be selected or rejected. Their use is advocated in preference to other filters which are commonly used in quantitative economic analysis.

Social information is particularly prominent in digital settings where the design of platforms can more easily give real-time information about the behaviour of peers and reference groups and thereby stimulate political activity. Changes to these platforms can generate natural experiments allowing an assessment of the impact of changes in social information and design on participation. This pap...

The worldwide span of the microblogging service Twitter gives an opportunity to make international comparisons of trending topics of interest, such as news stories. Previous international comparisons of news interests have tended to use surveys and may bypass topics not well covered in the mainstream media. This article uses 9 months of English tweets from the UK, USA, India, South Africa, New ...

Most messages posted in Twitter usually discuss an ongoing event, triggering a series of tweets that together may constitute a trending topic (e.g., #election2012, #jesuischarlie, #oscars2016). Sometimes, such a topic may be trending only locally, assuming that related posts have a geographical reference, either directly geotagging them with exact coordinates or indirectly by mentioning a well-...

Many search engines identify bursts of activity around particular topics and reflect these back to users as Popular Now or Hot Searches. Activity around these topics typically evolves quickly in real-time during the course of a trending event. Users’ informational needs when searching for such topics will vary depending on the stage at which they engage with an event. Through a survey and log s...

Challenging pharmaceutical manufacturers everywhere, every day are the myriad issues surrounding the acquisition, disposition and analysis of the huge amounts of data their operations create around the clock. Any Pharma producer worth its salt these days is likely investing a great deal of time, resources and effort to create or maintain a comprehensive information technology (IT) infrastructur...