As part of my work for a Dutch regional government, I was asked to compare the open data offerings of the 12 provinces. I wanted to use something that levels the playing field for all parties compared and prevents me comparing apples to oranges, so opted for the Dutch national data portal as a source of data. An additional benefit of this is that the Dutch national portal (a CKAN instance) has a well defined API, and uses standardised vocabularies for the different government entities and functions of government.

I am interested in openness, findability, completeness, re-usability, and timeliness. For each of those I tried to pick something available through the API, that can be a proxy for one or more of those factors.

The following aspects seemed most useful:

  • openness: use of open licenses
  • findability: are datasets categorised consistently and accurately so they can be found through the policy domains they pertain to
  • completeness: does a province publish across the entire spectrum of a) national government’s list of policy domains, and b) across all 7 core tasks as listed by the association of provincial governments
  • completeness: does a province publish more than just geographic data (most of their tasks are geo-related, but definitely not all)
  • re-usability: in which formats do provinces publish, and are these a) open standards, b) machine readable, c) structured data

I could not establish a useful proxy for timeliness, as all the timestamps available through the API of the national data portal actually represent processes (when the last automatic update ran), and contain breaks (the platform was updated late last year, and all timestamps were from after that update).

Provinces publish data in three ways, and the API of the national portal makes the source of a dataset visible:

  1. they publish geographic data to the Dutch national geographic register (NGR), from which metadata is harvested into the Dutch open data portal. It used to be that only openly licensed data was harvested but since November last year also closed licensed data is being harvested into the national portal. It seems this is done by design, but this major shift has not been communicated at all.
  2. they publish non-geographic data to, a CKAN platform provided as a commercial service to government entities to host open data (as the national portal only registers metadata, and isn’t storing data). Metadata is automatically harvested into the national portal.
  3. they upload metadata directly to the national portal by hand, pointing to specific data sources online elsewhere (e.g. the API of an image library)

Most provinces only publish through the National Geo Register (NGR). Last summer I blogged about that in more detail, and nothing has changed really since then.

I measured the mentioned aspects as follows:

  • openness: a straight count of openly licensed data sets. It is national policy to use public domain, CC0 or CC-BY, and this is reflected in what provinces do. So no need to distinguish between open licenses, just between open and not-openly licensed material
  • findability: it is mandatory to categorise datasets, but voluntary to add more than one category, with a maximum of 3. I looked at the average number of categories per dataset for each province. One only categorises with one term, some consistently provide more complete categorisation, where most end up in between those two.
  • completeness: looking at those same categories, a total of 22 different ones were used. I also looked at how many of those 22 each province uses. As all their tasks are similar, the extend to which they cover all used categories is a measure for how well they publish across their spectrum of tasks. Additionally provinces have self-defined 7 core tasks, to which those categories can be mapped. So I also looked at how many of those 7 covered. There are big differences in the breadth of scope of what provinces publish.
  • completeness: while some 80% of all provincial data is geo-data and 20% non-geographic, less than 1% of open data is non-geographic data. Looking at which provinces publish non-geographic data, I used the source of it (i.e. not from the NGR), and did a quick manual check on the nature of what was published (as it was just 22 data sets out of over 3000, this was still easily done by hand).
  • re-usability: for all provinces I polled the formats in which data sets are published. Data sets can be published in multiple formats. All used formats I judged on being a) open standards, b) machine readable, c) structured data. Formats that matched all 3 got 3 points, that matched machine readable and structure but not open standards 1 points, and didn’t match structure or machine readability no points. I then divided the number of points by the total number of data formats they used. This way you get a score of at most 3, and the closer you get to 3, the more of your data matches the open definition.

As all this is based on the national portal’s API, getting the data and calculating scores can be automated as an ongoing measurement to build a time series of e.g. monthly checks to track development. My process only contained one manual action (concerning non-geo data), but it could be done automatically followed up at most with a quick manual inspection.

In terms of results (which now have been first communicated to our client), what becomes visible is that some provinces score high on a single measure, and it is easy to spot who has (automated) processes in place for one or more of the aspects looked at. Also interesting is that the overall best scoring province is not the best scoring on any of the aspects but high enough on all to have the highest average. It’s also a province that spent quite a lot of work on all steps (internally and publication) of the chain that leads to open data.

9 reactions on “Measuring Open Data Quality of Dutch Provinces

  1. Dankjewel voor het delen van je bevindingen!
    Ik ben nu bezig met iets wat hier op aansluit: voor een kleine steekproef van open datasets van de provincie Groningen onderzoek ik of er andere online (open) datasets te vinden zijn, en in hoeverre die afwijken. Het gaat me hierbij dus om de data-integriteit.
    Voor een aantal datasets zijn er landelijke of interprovinciale registraties, en deelt de provincie de gegevens zelf óók als open data. Als het data management niet op orde is, kunnen hierbij problemen ontstaan. Hetzelfde zie je *binnen* de organisatie, bij datasets waar verschillende afdelingen zich eigenaar van voelen. In dat geval ligt het probleem ook bij het ontbreken van goede data governance.

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