Tag Archives: DDJ

Inter-Council Payments and the Google Fusion Tables Network Graph

One of the great things about aggregating local spending data from different councils in the same place – such as on OpenlyLocal – is that you can start to explore structural relations in the way different public bodies of a similar type spend money with each other.

On the local spend with corporates scraper on Scraperwiki, which I set up to scrape how different councils spent money with particular suppliers, I realised I could also use the scraper to search for how councils spent money with other councils, by searching for suppliers containing phrases such as “district council” or “town council”. (We could also generate views to to see how councils wre spending money with different police authorities, for example.)

(The OpenlyLocal API doesn’t seem to work with the search, so I scraped the search results HTML pages instead. Results are paged, with 30 results per page, and what seems like a maximum of 1500 (50 pages) of results possible.)

The publicmesh table on the scraper captures spend going to a range of councils (not parish councils) from other councils. I also uploaded the data to Google Fusion tables (public mesh spending data), and then started to explore it using the new network graph view (via the Experiment menu). So for example, we can get a quick view over how the various county councils make payments to each other:

Hovering over a node highlights the other nodes its connected to (though it would be good if the text labels from the connected nodes were highlighted and labels for unconnected nodes were greyed out?)

(I think a Graphviz visualisation would actually be better, eg using Canviz, because it can clearly show edges from A to B as well as B to A…)

As with many exploratory visualisations, this view helps us identify some more specific questions we might want to ask of the data, rather than presenting a “finished product”.

As well as the experimental network graph view, I also noticed there’s a new Experimental View for Google Fusion Tables. As well as the normal tabular view, we also get a record view, and (where geo data is identified?) a map view:

What I’d quite like to see is a merging of map and network graph views…

One thing I noticed whilst playing with Google Fusion Tables is that getting different aggregate views is rather clunky and relies on column order in the table. So for example, here’s an aggregated view of how different county councils supply other councils:

In order to aggregate by supplied council, we need to reorder the columns (the aggregate view aggregates columns as thet appear from left to right in the table view). From the Edit column, Modify Table:

(In my browser, I then had to reload the page for the updated schema to be reflected in the view). Then we can get the count aggregation:

It would be so much easier if the aggregation view allowed you to order the columns there…

PS no time to blog this properly right now, but there are a couple of new javascript libraries that are worth mentioning in the datawrangling context.

In part coming out of the Guardian stable, Misoproject is “an open source toolkit designed to expedite the creation of high-quality interactive storytelling and data visualisation content”. The initial dataset library provides a set of routines for: loading data into the browser from a variety of sources (CSV, Google spreadsheets, JSON), including regular polling; creating and managing data tables and views of those tables within the browser, including column operations such as grouping, statistical operations (min, max, mean, moving average etc); playing nicely with a variety of client side graphics libraries (eg d3.js, Highcharts, Rickshaw and other JQuery graphics plugins).

Recline.js is a library from Max Ogden and the Open Knowledge Foundation that if its name is anything to go by is positioning itself as an alternative (or complement?) to Google Refine. To my mind though, it’s more akin to a Google Fusion Tables style user interface (“classic” version) wherever you need it, via a Javascript library. The data explorer allows you to import and preview CSV, Excel, Google Spreadsheet and ElasticSearch data from a URL, as well as via file upload (so for example, you can try it with the public spend mesh data CSV from Scraperwiki). Data can be sorted, filtered and viewed by facet, and there’s a set of integrated graphical tools for previewing and displaying data too. Refine.js views can also be shared and embedded, which makes this an ideal tool for data publishers to embed in their sites as a way of facilitating engagement with data on-site, as I expect we’ll see on the Data Hub before too long.

More reviews of these two libraries later…

PPS These are also worth a look in respect of generating visualisations based on data stored in Google spreadsheets: DataWrapper and Freedive (like my old Guardian Datastore explorer, but done properly… Wizard led UI that helps you create your own searchable and embeddable database view direct from a Google Spreadsheet).

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Accessing and Visualising Sentencing Data for Local Courts

A recent provisional data release from the Ministry of Justice contains sentencing data from English(?) courts, at the offence level, for the period July 2010-June 2011: “Published for the first time every sentence handed down at each court in the country between July 2010 and June 2011, along with the age and ethnicity of each offender.” Criminal Justice Statistics in England and Wales [data]

In this post, I’ll describe a couple of ways of working with the data to produce some simple graphical summaries of the data using Google Fusion Tables and R…

…but first, a couple of observations:

– the web page subheading is “Quarterly update of statistics on criminal offences dealt with by the criminal justice system in England and Wales.”, but the sidebar includes the link to the 12 month set of sentencing data;
– the URL of the sentencing data is http://www.justice.gov.uk/downloads/publications/statistics-and-data/criminal-justice-stats/recordlevel.zip, which does not contain a time reference, although the data is time bound. What URL will be used if data for the period 7/11-6/12 is released in the same way next year?

The data is presented as a zipped CSV file, 5.4MB in the zipped form, and 134.1MB in the unzipped form.

The unzipped CSV file is too large to upload to a Google Spreadsheet or a Google Fusion Table, which are two of the tools I use for treating large CSV files as a database, so here are a couple of ways of getting in to the data using tools I have to hand…

Unix Command Line Tools

I’m on a Mac, so like Linux users I have ready access to a Console and several common unix commandline tools that are ideally suited to wrangling text files (on Windows, I suspect you need to install something like Cygwin; a search for windows unix utilities should turn up other alternatives too).

In Playing With Large (ish) CSV Files, and Using Them as a Database from the Command Line: EDINA OpenURL Logs and Postcards from a Text Processing Excursion I give a couple of examples of how to get started with some of the Unix utilities, which we can crib from in this case. So for example, after unzipping the recordlevel.csv document I can look at the first 10 rows by opening a console window, changing directory to the directory the file is in, and running the following command:

head recordlevel.csv

Or I can pull out rows that contain a reference to the Isle of Wight using something like this command:

grep -i wight recordlevel.csv > recordsContainingWight.csv

(The -i reads: “ignoring case”; grep is a command that identifies rows contain the search term (wight in this case). The > recordsContainingWight.csv says “send the result to the file recordsContainingWight.csv” )

Having extracted rows that contain a reference to the Isle of Wight into a new file, I can upload this smaller file to a Google Spreadsheet, or as Google Fusion Table such as this one: Isle of Wight Sentencing Fusion table.

Isle fo wight sentencing data

Once in the fusion table, we can start to explore the data. So for example, we can aggregate the data around different values in a given column and then visualise the result (aggregate and filter options are available from the View menu; visualisation types are available from the Visualize menu):

Visualising data in google fusion tables

We can also introduce filters to allow use to explore subsets of the data. For example, here are the offences committed by females aged 35+:

Data exploration in Google FUsion tables

Looking at data from a single court may be of passing local interest, but the real data journalism is more likely to be focussed around finding mismatches between sentencing behaviour across different courts. (Hmm, unless we can get data on who passed sentences at a local level, and look to see if there are differences there?) That said, at a local level we could try to look for outliers maybe? As far as making comparisons go, we do have Court and Force columns, so it would be possible to compare Force against force and within a Force area, Court with Court?

R/RStudio

If you really want to start working the data, then R may be the way to go… I use RStudio to work with R, so it’s a simple matter to just import the whole of the reportlevel.csv dataset.

Once the data is loaded in, I can use a regular expression to pull out the subset of the data corresponding once again to sentencing on the Isle of Wight (i apply the regular expression to the contents of the court column:

recordlevel <- read.csv("~/data/recordlevel.csv")
iw=subset(recordlevel,grepl("wight",court,ignore.case=TRUE))

We can then start to produce simple statistical charts based on the data. For example, a bar plot of the sentencing numbers by age group:

age=table(iw$AGE)
barplot(age, main="IW: Sentencing by Age", xlab="Age Range")

R - bar plot

We can also start to look at combinations of factors. For example, how do offence types vary with age?

ageOffence=table(iw$AGE, iw$Offence_type)
barplot(ageOffence,beside=T,las=3,cex.names=0.5,main="Isle of Wight Sentences", xlab=NULL, legend = rownames(ageOffence))

R barplot - offences on IW

If we remove the beside=T argument, we can produce a stacked bar chart:

barplot(ageOffence,las=3,cex.names=0.5,main="Isle of Wight Sentences", xlab=NULL, legend = rownames(ageOffence))

R - stacked bar chart

If we import the ggplot2 library, we have even more flexibility over the presentation of the graph, as well as what we can do with this sort of chart type. So for example, here’s a simple plot of the number of offences per offence type:

require(ggplot2)
#You may need to install ggplot2 as a library if it isn't already installed
ggplot(iw, aes(factor(Offence_type)))+ geom_bar() + opts(axis.text.x=theme_text(angle=-90))+xlab('Offence Type')

GGPlot2 in R

Alternatively, we can break down offence types by age:

ggplot(iw, aes(AGE))+ geom_bar() +facet_wrap(~Offence_type)

ggplot facet barplot

We can bring a bit of colour into a stacked plot that also displays the gender split on each offence:

ggplot(iw, aes(AGE,fill=sex))+geom_bar() +facet_wrap(~Offence_type)

ggplot with stacked factor

One thing I’m not sure how to do is rip the data apart in a ggplot context so that we can display percentage breakdowns, so we could compare the percentage breakdown by offence type on sentences awarded to males vs. females, for example? If you do know how to do that, please post a comment below šŸ˜‰

PS HEre’s an easy way of getting started with ggplot… use the online hosted version at http://www.yeroon.net/ggplot2/ using this data set: wightCrimRecords.csv; download the file to your computer then upload it as shown below:

yeroon.net/ggplot2

PPS I got a little way towards identifying percentage breakdowns using a crib from here. The following command:
iwp=tapply(iw$Offence_type,iw$sex,function(x){prop.table(table(x))})
generates a (multidimensional) array for the responseVar (Offence) about the groupVar (sex). I don’t know how to generate a single data frame from this, but we can create separate ones for each sex as follows:
iwpMale=data.frame(iwp['Male'])
iwpFemale=data.frame(iwp['Female'])

We can then plot these percentages using constructions of the form:
ggplot(iwp2)+geom_bar(aes(x=Male.x,y=Male.Freq))
What I haven’t worked out how to do is elegantly map from the multidimensional array to a single data.frame? If you know how, please add a comment below…(I also posted a question on Cross Validated, the stats bit of Stack Exchange…)

Data Referenced Journalism and the Media ā€“ Still a Long Way to Go Yet?

Reading our local weekly press this evening (the Isle of Wight County Press), I noticed a page 5 headline declaring “Alarm over death rates at St Mary’s”, St Mary’s being the local general hospital. It seems a Department of Health report on hospital mortality rates came out earlier this week, and the Island’s hospital, it seems, has not performed so well…

Seeing the headline – and reading the report – I couldn’t help but think of Ben Goldacre’s Bad Science column in the Observer last week (DIY statistical analysis: experience the thrill of touching real data ), which commented on the potential for misleading reporting around bowel cancer death rates; among other things, the column described a statistical graphic known as a funnel plot which could be used to support the interpretation of death rate statistics and communicate the extent to which a particular death rate, for a given head of population, was “significantly unlikely” in statistical terms given the distribution of death rates across different population sizes.

I also put together a couple of posts describing how the funnel plot could be generated from a data set using the statistical programming language R.

Given the interest there appears to be around data journalism at the moment (amongst the digerati at least), I thought there might be a reasonable chance of finding some data inspired commentary around the hospital mortality figures. So what sort of report was produced by the Guardian (Call for inquiries at 36 NHS hospital trusts with high death rates) or the Telegraph (36 hospital trusts have higher than expected death rates), both of which have pioneering data journalists working for them, come up with? Little more than the official press release: New hospital mortality indicator to improve measurement of patient safety.

The reports were both formulaic, picking on leading with the worst performing hospital (which admittedly was not mentioned in the press release) and including some bog standard quotes from the responsible Minister lifted straight out of the press release (and presumably written by someone working for the Ministry…) Neither the Guardian nor the Telegraph story contained a link to the original data, which was linked to from the press release as part of the Notes to editors rider.

If we do a general, recency filtered, search for hospital death rates on either Google web search:

UK hosptial death rates reporting

or Google news search:

UK hospital death rate reporting

we see a wealth of stories from various local press outlets. This was a story with national reach and local colour, and local data set against a national backdrop to back it up. Rather than drawing on the Ministerial press released quotes, a quick scan of the local news reports suggests that at least the local journalists made some effort compared to the nationals’ churnalism, and got quotes from local NHS spokespeople to comment on the local figures. Most of the local reports I checked did not give a link to the original report, or dig too deeply into the data. However, This is Tamworth, (which had a Tamworth Herald byline in the Google News results), did publish the URL to the full report in its article Shock report reveals hospital has highest death rate in country, although not actually as a link… Just by the by, I also noticed the headline was flagged with a “Trusted Source” badge:

WHich is the trusted source?

Is that Tamworth Herald as the trusted source, or the Department of Health?!

Given that just a few days earlier, Ben Goldacre had provided an interesting way of looking at death rate data, it would have been nice to think that maybe it could have influenced someone out there to try something similar with the hospital mortality data. Indeed, if you check the original report, you can find a document describing How to interpret SHMI bandings and funnel plots (although, admittedly, not that clearly perhaps?). And along with the explanation, some example funnel plots.

However, the plots as provided are not that useful. They aren’t available as image files in a social or rich media press release format, nor are statistical analysis scripts that would allow the plots to be generated from the supplied data in too like R; that is to say, the executable working wasn’t shown…

So here’s what I’m thinking: firstly, we need data press officers as well as data journalists. Their job would be to put together the tools that support the data churnalist in taking the raw data and producing statistical charts and interpretation from it. Just like the ministerial quote can be reused by the journalist, so the data press pack can be used to hep the journalist get some graphs out there to help them illustrate the story. (The finishing of the graph would be up to the journalist, but the mechanics of the generation of the base plot would be provided as part of the data press pack.)

Secondly, there may be an opportunity for an enterprising individual to take the data sets and produced localised statistical graphics from the source data. In the absence of a data press officer, the enterprising individual could even fulfil this role. (To a certain extent, that’s what the Guardian Datastore does.)

(Okay, I know: the local press will have allocated only a certain amount of space to the story, and the editor would likely see any mention of stats or funnel plots as scaring folk off, but we have to start changing attitudes, expectations, willingness and ability to engage with this sort of stuff somehow. Most people have very little education in reading any charts other than pie charts, bar charts, and line charts, and even then are easily misled. We have start working on this, we have to start looking at ways of introducing more powerful plots and charts and helping people get a folk understanding of them. And funnel plots may be one of the things we should be starting to push?)

Now back to the hospital data. In How Might Data Journalists Show Their Working? Sweave, I posted a script that included the working for generating a funnel plot from an appropriate online CSV data source. Could this script be used to generate a funnel plot from the hospital data?

I had a quick play, and managed to get a scatterplot distribution that looks like the one on the funnel plot explanation guide by setting the number value to the SHMI Indicator data (csv) EXPECTED column and the p to the VALUE column. However, because the p value isn’t a probability in the range 0..1, the p.se calculation fails:
p.se <- sqrt((p*(1-p)) / (number))

Anyway, here’s the script for generating the straightforward scatter plot (I had to read the data in from a local file because there was some issue with the security certificate trying to read the data in from the online URL using the RCurl library and hospitaldata = data.frame( read.csv( textConnection( getURL( DATA_URL ) ) ) ):

hospitaldata = read.csv("~/Downloads/SHMI_10_10_2011.csv")
number = hospitaldata$EXPECTED
p = hospitaldata$VALUE
df = data.frame(p, number, Area=hospitaldata$PROVIDER.NAME)
ggplot(aes(x = number, y = p), data = df) + geom_point(shape = 1)

There’s presumably a simple fix to the original script that will take the range of the VALUE column into account and allow us to plot the funnel distribution lines appropriately? If anyone can suggest the fix, please let me know in a comment…;-)

How Might Data Journalists Show Their Working? Sweave

If part of the role of data journalism is to make transparent the justification behind claims that are, or aren’t, backed up by data, there’s good reason to suppose that the journalists should be able to back up their own data-based claims with evidence about how they made use of the data. Posting links to raw data helps to a certain extent – at least third parties can then explore the data themselves and check the claims the press are making – but you could also argue that the journalists should also make their notes available regarding how they worked the data. (The same is true in public reports, where summary statistics and charts are included in a report, along with a link to the raw data, but no transparency in how the summary reports/charts were actually produced from the data.)

In Power Tools for Aspiring Data Journalists: R, I explored how we might use the R statistical programming language to replicate a chart that appeared in one of Ben Goldacre’s Bad Science columns. I included code snippets in the post, along with the figures they generated. But is there a way of getting even closer to the source, as it were, and produce documents that essentially generate their output from some sort of “source code”?

For example, take this view of my working relating to the production of the funnel chart described in Goldacre’s column:

You can find the actual “source code” for that document here: bowel cancer funnel plot working notes If you load it into something like RStudio, you can “run” the code and generate your own PDF from it.

The “source” of the document includes both text and R code. When the Sweave document is processed, the R code contained within the document is executed and the results also included in the document. The charts shown in the report are generated directly from the code included in the document, using data pulled in to the document form a source referenced within the document. If the source data is changed, or the R code is changed, what’s contained in the output document will change as well.

This sort of workflow will be familiar to many experimental scientists, but I wonder: is it something that data journalists have considered, at least as a way of keeping working notes about data related projects they are working on?

PS as well as Sweave, see dexy.it, which generalises the Sweave approach to allow you to create self-documenting software/code. Educators, also take note…;-)

Active Lobbying Through Meetings with UK Government Ministers

In a move that seemed to upset collectors of UK ministerial meeting data, @whoslobbying, on grounds of wasted effort, the Guardian datastore published a spreadsheet last night containing data relating to ministerial meetings between May 2010 and March 2011.

(The first release of the spreadsheet actually omitted the column containing who the meeting was with, but that seems to be fixed now… There are, however, still plenty of character encoding issues (apostrophes, accented characters, some sort of em-dash, etc) that might cripple some plug and play tools.)

Looking over the data, we can use it as the basis for a network diagram with actors (Ministers and lobbiests) with edges representing meetings between Minsiters and lobbiests. There is one slight complication in that where there is a meeting between a Minister and several lobbiests, we ideally need to separate out the separate lobbiests into their own nodes.

UK gov meetings spreadsheet

This probably provides an ideal opportunity to have a play with the Stanford Data Wrangler and try forcing these separate lobbiests onto separate rows, but I didn’t allow myself much time for the tinkering (and the requisite learning!), so I resorted to Python script to read in the data file and split out the different lobbiests. (I also did an iterative step, cleaning the downloaded CSV file in a text editor by replacing nasty characters that caused the script to choke.) You can find the script here (note that it makes use of the networkx network analysis library, which you’ll need to install if you want to run the script.)

The script generates a directed graph with links from Ministers to lobbiests and dumps it to a GraphML file (available here) that can be loaded directly into Gephi. Here’s a view – using Gephi – of the hearth of the network. If we filter the graph to show nodes that met with at least five different Ministers…

Gephi - k-core filter

we can get a view into the heart of the UK lobbying netwrok:

Active Lobbiests

I sized the lobbiest nodes according to eigenvector centrality, which gives an indication of well connected they are in the network.

One of the nice things about Gephi is that it allows for interactive exploration of a graph, For example, I can hover over a lobbiest node – Barclays in this case – to see which Ministers were met:

Bankers connect...

Alternatively, we can see who of the well connected met with the Minister for Welfare Reform:

Welfare meetings...

Looking over the data, we also see how some Ministers are inconsistently referenced within the original dataset:

Multiple mentions

Note that the layout algorithm is such that the different representations of the same name are likely to meet similar lobbiests, which will end up placing the node in a similar location under the force directed layout I used. Which is to say – we may be able to use visual tools to help us identify fractured representations of the same individual. (Note that multiple meetings between the same parties can be visualised using the thickness of the edges, which are weighted according to the number of times the edge is described in the GraphML file…)

Unifying the different representations of the same indivudal is something that Google Refine could help us tidy up with its various clustering tools, although it would be nice if the Datastore folk addressed this at source (or at least, as part of an ongoing data quality enhancement process…;-)

I guess we could also trying reconciling company names against universal company identifiers, for example by using Google Refine’s reconciliation service and the Open Corporates database? Hmmm, which makes me wonder: do MySociety, or Public Whip, offer an MP or Ministerial position reconciliation service that works with Google Refine?

A couple of things I haven’t done: represented the department (which could be done via a node attribute, maybe, at least for the Ministers); represented actual meetings, and what I guess we might term co-lobbying behaviour, where several organisations are in the same meeting.

Dutch regional newspapers launch data journalism project RegioHack

In a guest post for OJB, Jerry Vermanen explains the background to RegioHack

The internet is bursting with information, but journalists – at least in The Netherlands – don’t get the full potential out of it. Basic questions on what data driven journalism is, and how to practise it, still have to be answered. Two Dutch regional newspapers (de Stentor and TC Tubantia) have launched RegioHack, an experiment with data driven journalism around local issues and open data.

Both newspapers circulate in the eastern and middle part of the Netherlands.Ā In November, journalists will collaborate with local students, programmers and open data experts in a 30 hour coding event.Ā In preparation for this hackathon, the forum on our website (www.regiohack.nl) is opened for discussion. Anyone can start a thread for a specific problem. For example, what’s the average age of each town in our region? And in 10 years, do we have enough facilities to accommodate the future population? And if not, what do we need?

The newspapers provide the participants with hot pizza, energy drink and 30 hours to find, clean up and present the data on these subjects.

After the hackathon, the projects are presented and participants will be named in the publications. That’s what RegioHack is all about: making unique stories with data, helping each other to develop new skills and finding out how to practise data driven journalism.

If you happen to be in The Netherlands on November 10th and 11th, contact me on jerry@regiohack.nl or Twitter (@JerryVermanen) for an invite to the final presentation.

We’re also searching for guest bloggers – and yes, that can be in English.

Data Journalists Engaging in Co-Innovationā€¦

You may or may not have noticed that the Boundary Commission released their take on proposed parliamentary constituency boundaries today.

They could have released the data – as data – in the form of shape files that can be rendered at the click of a button in things like Google Maps… but they didn’t… [The one thing the Boundary Commission quango forgot to produce: a map] (There are issues with publishing the actual shapefiles, of course. For one thing, the boundaries may yet change – and if the original shapefiles are left hanging around, people may start to draw on these now incorrect sources of data once the boundaries are fixed. But that’s a minor issue…)

Instead, you have to download a series of hefty PDFs, one per region, to get a flavour of the boundary changes. Drawing a direct comparison with the current boundaries is not possible.

The make-up of the actual constituencies appears to based on their member wards, data which is provided in a series of spreadsheets, one per region, each containing several sheets describing the ward makeup of each new constituency for the counties in the corresponding region.

It didn’t take long for the data junkies to get on the case though. From my perspective, the first map I saw was on the Guardian Datastore, reusing work by University of Sheffield academic Alasdair Rae, apparently created using Google Fusion Tables (though I haven’t see a recipe published anywhere? Or a link to the KML file that I saw Guardian Datablog editor Simon Rogers/@smfrogers tweet about?)

[I knew I should have grabbed a screen shot of the original map…:-(]

It appears that Conrad Quilty-Harper (@coneee) over at the Telegraph then got on the case, and came up with a comparative map drawing on Rae’s work as published on the Datablog, showing the current boundaries compared to the proposed changes, and which ties the maps together so the zoom level and focus are matched across the maps (MPs’ constituencies: boundary changes mapped):

Telegraph side by side map comparison

Interestingly, I was alerted to this map by Simon tweeting that he liked the Telegraph map so much, they’d reused the idea (and maybe even the code?) on the Guardian site. Here’s a snapshot of the conversation between these two data journalists over the course of the day (reverse chronological order):

Datajournalists in co-operative bootstrapping mode

Here’s the handshake…

Collaborative co-evolution

I absolutely love this… and what’s more, it happened over the course of four or five hours, with a couple of technology/knowledge transfers along the way, as well as evolution in the way both news agencies communicated the information compared to the way the Boundary Commission released it. (If I was evil, I’d try to FOI the Boundary Commission to see how much time, effort and expense went into their communication effort around the proposed changes, and would then try to guesstimate how much the Guardian and Telegraph teams put into it as a comparison…)

At the time of writing (15.30), the BBC have no data driven take on this story…

And out of interest, I also wondered whether Sheffield U had a take…

Sheffiled u media site

Maybe not…

PS By the by, the DataDrivenJournalism.net website relaunched today. I’m honoured to be on the editorial board, along with @paulbradshaw @nicolaskb @mirkolorenz @smfrogers and @stiles, and looking forward to seeing how we can start to drive interest, engagement and skills development in, as well as analysis and (re)use of, and commentary on, public open data through the data journalism route…

PPS if you’re into data journalism, you may also be interested in GetTheData.org, a question and answer site in the model of Stack Overflow, with an emphasis on Q&A around how to find, access, and make use of open and public datasets.