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Update on the Witan Project

The Witan project kicked off this summer with a flurry of meetings, workshops, brainstorming sessions and lofty aspirations.  Out of this frothy mix came the pragmatic decision to aim for concrete deliverables which both demonstrated the project’s potential and offered real benefit to stakeholders.  Demography was chosen as the field on which to focus first – a decision reflecting the pivotal role of demographic projections to planning work in London.

First steps

An initial tranche of work has been planned with the goal of delivering what is being referred to as the Minimum Viable Product (MVP).  The aim with the MVP was to identify a combination of functionality and features that could realistically be built in a short time frame and still yield tangible benefits.  The key feature of the MVP is a web-based interface through which London local authorities can produce population projections to order.

The Demography Team currently spent a lot of time each year producing projections for various purposes.  As well as those made publicly available via the London Datastore, it also produces bespoke outputs for individual authorities based on their choice of housing development scenarios.  Although we’ve made improvements over the years automate and streamline the projection process, these improvements haven’t kept step with growing demand for outputs.  As a result we have to turn down a number of requests to produce projections each year due to resourcing constraints.

Through the MVP we hope to achieve clear benefits for both the projections team – reducing the time spent producing outputs; and for local authority users, who will gain the ability to produce outputs on demand to meet their needs.

Collaborative working

As the collaboration began in earnest, the Mastodon team conducted a series of interviews with members of the Demography Team to understand what it is we actually do. After an introduction into the intricate and rather arcane field of demographic projections, Mastodon began to map out our models, processes and outputs. We’re now working with them to translate our models – an eclectic mix of Excel workbooks and code built up over the decades – ready for integration into the new platform.  At the same time, Mastodon is developing the underlying infrastructure of the platform and meeting with users to inform the design of the interface.


An early attempt to map out the modelling process

Working with a specialist technology SME has been interesting for those of us used to the world of local government.  The Mastodon team make great use of technology work to coordinate and collaborate.  It took a little while for us to get used to Slack and GitHub, but they’re already proving invaluable for joint work on the project.  These tools allow us to easily follow the Mastodon team’s progress, review code, and answer methodological questions as they arise.


The fascinating world of the Witan Project Slack channel

It’s a far cry from the way we’re used to working in local government and presents us with an opportunity for us to learn from the private sector and bring those lessons back to City Hall.

Next steps

The MVP launch later this year will mark an early milestone in the project.  Thoughts have already turned to next steps and what can be achieved in the time available.

We’re currently putting the finishing touches to our plans to expand the geographical scope of our projection models out beyond London’s boundaries.  We see this as a key step necessary to better support a range of future planning activity – all of which will benefit from the ability to produce consistent projection scenarios for the wider region and beyond.

Prior to the announcement of Witan, implementing the expanded model had looked to be a big task in its own right.  While most aspects of the model scale up easily as more areas are added, the demands of domestic migration modelling rapidly become unwieldy with our current systems.  The development of the Witan platform is therefore good timing for us – the architecture Mastodon have designed should shrug off the extra processing demands as well as helping us to manage the ever larger volume of data flowing in and out of the models.

Beyond that we’re looking to explore linkages with other models we use at the GLA, but that’s a topic for another day.

The GLA demography team is currently recruiting for a modelling specialist to work with us on Witan and other exciting projects. If you’re interested in applying your skills to real world problems then please get in touch with us.

Ben Corr is the Demography Manager in GLA Intelligence Unit.