Showing posts with label development. Show all posts
Showing posts with label development. Show all posts

Monday, 22 June 2015

Where is all London's new housing?

Some of my recent work on housing markets, mortgage lending and housing search has led me to consider the question of where, exactly, London's new housing is located. On a recent visit to King's Cross I was amazed by the sheer scale of development, particularly all the new flats. Because I've been working with the data for another project - and recently re-examined it for a project proposal which explicitly didn't focus on London - I thought it would be interesting to see whether my perception of the flats boom is based in reality. Of course it is! 

The maps below are based on all new build homes sold in London from 1 June 2010 to the end of April 2015 (the most recent data). During this time, according to HM Land Registry 'price paid' data, there were 42,938 transactions on 42,813 properties. This indicates that quite a few properties are not being picked up in this dataset - e.g. compare it to the completions data from the London Datastore. Nevertheless, the patterns and distribution of property types is revealing. 88.8% of transactions were for flats, 7.1% for terraced houses, 2.4% for semi-detached properties and 1.7% for detached houses.

All property types

Flats

Terraced houses

Semi-detached houses

Detached houses


Clearly, the mix of new housing - and its relative low volume - is something that many people have commented on before, but I've not seen many people look at the geographical distribution in this way. The important questions arising from these maps - as ever - is why are things the way they are? That's something the maps can't tell us but it does provide an interesting starting point for debate. The discrepancy between the Land Registry data and data on completions is also not surprising owing to the way new build housing is sometimes sold, but it would be interesting to explore this more in future. If you do happen to have a few million quid to spare, good luck finding a new detached London house to live in!

A note on the maps... I've geocoded the price paid data using Ordnance Survey's Code-Point Open dataset, which can match sales to postcode units, rather than street addresses. The transparent bubble map is of course far from perfect but I've used it here to convey the scale and location of new housing, rather than to offer a precise fix. So long as it gives the impression of there being a massive splodge of newbuild flats in Central London that'll do for now. I am aiming to highlight the general scale and geography of development as a fairly quick experiment to see what might be done with the data. No plans to make it interactive (update: the best laid plans of... see map point datadump below).



Update (1715, 22 June 2015): I fixed the glitches, which were caused by a rogue space here and there in the codepoint open file. Moral of the story? Build more houses (I think). Always a giveaway when there aren't many dots in Wandsworth. The numbers were correct all along though. Finally, I've added in some information from HM Land Registry on properties not included in the price paid data.


Data excluded from Price Paid dataset - link




Monday, 11 June 2012

The Population of China

In a few weeks I will be travelling to China for a conference, where I'm co-presenting a paper on regional inequalities in China and the EU. This has meant I've had to get hold of lots of Chinese datasets, some of which I have produced maps from - so I thought I'd post one or two here, along with some facts and figures. I should point out that most of the data I've been using has come from the National Bureau of Statistics of China website. 

Higher resolution version

In this 3D map I've just extruded the surface using population density data at a very local level. This required a reasonable amount of computing power but the effect is simply to emphasise the significant West/East split in population within China. This geographical division has been the topic of discussion for a long time and in relation to a number of areas but is generally referred to as the Hu Huanyong line (also sometimes the Hu line, Heihe-Tengchong Line or Aihui-Tengchong Line), after the Chinese population geographer of the same name. Strangely enough, there is a Facebook page dedicated to the Hu line. The line divides China roughly into two parts. In 1935 when Hu first identified the split, the West had 57% of the area and 4% of the population. Today, the East has 94% of the population of China, but only 43% of the area. You can see how this looks in the map below... 


I'm still working on my parts of the presentation but am really fascinated by the facts and figures emerging from the 2010 Chinese census and data for different regions of China. China accounts for almost exactly 20% of the world population and both Beijing and Shanghai (i.e. the provinces) have 20 million or more people. I still need to learn a lot more about China, Chinese data and regional development there generally but my work so far suggests that patterns of regional inequality - while different in absolute terms - are often strikingly similar to patterns of regional inequality in Europe. A good example of this is in Jiangsu province, to the north of Shanghai.

Citations: Center for International Earth Science Information Network - CIESIN - Columbia University, International Food Policy Research Institute - IFPRI, The World Bank, and Centro Internacional de Agricultura Tropical - CIAT. 2011. Global Rural-Urban Mapping Project, Version 1 (GRUMPv1): Population Density Grid. Palisades, NY: NASA Socioeconomic Data and Applications Center (SEDAC). http://dx.doi.org/10.7927/H4R20Z93. Accessed 10 June 2012.

Balk, D.L., U. Deichmann, G. Yetman, F. Pozzi, S. I. Hay, and A. Nelson. 2006. Determining Global Population Distribution: Methods, Applications and Data. Advances in Parasitology 62:119-156. http://dx.doi.org/10.1016/S0065-308X(05)62004-0.


P.S. Thanks are due to Chunhua Liu for her insights here!