The main objective of the ProDataMarket project is to create a data marketplace for open and proprietary real-estate and related contextual data.
Marketplace is a place where data producers meet prospect data consumers. In addition to basic features for making data accessible and discoverable, marketplace can provide more tools to help data producers “advertise” their data and better engage with potential data consumers. Among such tools are those that help data producers explain the type of their data, its attributes and demonstrate its value. In this post we discuss how these tools are being realised in the ProDataMarket place.
Let’s consider a national statistical office, for example, the Italian National Institute of Statistics (ISTAT). ISTAT wants to disseminate one of its datasets, a dataset with census cells that cover the Italian region of Piemonte. This dataset subdivides the region of Piemonte in census sections according to ISTAT’s 2011 National Census. A census section is the smallest geographic unit for which the statistical variables of a population census are taken.
ISTAT is interested in explaining to the prospect data consumers that the data can be useful when it is needed to:
- determine inter-municipal boundaries
- describe different areas of a city in terms of some geographically-bound characteristics
Marketplace: initial steps
Figure 1 illustrates initial steps that ISTAT performs at the marketplace to present her data.
ISTAT prepares its data for publication, describes and catalogues it. Now, a prospect data consumer can discover and explore the dataset of census cells of the Piemonte region. While ISTAT made the data accessible and discoverable, data consumers still have to figure our themselves what type of data it is, what is inside and what is it useful for.
Marketplace: explaining the data types
To explain the type of the data, ISTAT creates and attaches visualisations to its data, as shown in Fig. 2.
In addition to preparing, describing and publishing Piemonte census sections dataset, ISTAT can create a map of all the census cells of the Piemonte region. This gives an illustrative example of the data to the prospect data consumers: when exploring the dataset, the data consumer can immediately see that the data contains polygons, each of which represents a geographic area of a census section.
Now that the type of the data is clearer, ISTAT can go further and explain various attributes of the data.
Marketplace: explaining attributes of the data
Figure 3 illustrates steps that ISTAT performs at the marketplace, to give the data consumers a glimpse of the data attributes.
As mentioned above, the dataset of the driving example contains census cells’ geometries. Every cell is attach to a certain municipality. This information becomes useful if one wants to represent single municipalities on a map. For example, to represent the city of Turin, ISTAT can prepare a subset of the census cells by filtering on the municipality attribute of each cell. Similarly, other attributes of the data can be highlighted.
Marketplace: putting data into context to explain its value
With the help of the marketplace, ISTAT can prepare, describe and visualise as many subsets of the data, as she wants to. Finally, to showcase the value of the data and explain to the data consumer its value, ISTAT can put census cells into context, as illustrated in Fig. 4.
This last approach is realised through the Augmentation Service that supports querying a co-located data source using several functions to produce a new dataset. Currently, the Augmentation Service uses data from OpenStreetMap, to provide context. For example, ISTAT can use the service to extract the number of bus stops found nearby each census cell, or the distance to the closest train station, or the length of pedestrian paths in each census cell. Once the new augmented dataset is prepared, ISTAT can proceed with visualisations. For example, she can create a coloured map to show density of nearby bus stops in Turin.