Metadata – use

data discovery e.g. a library catalog

data assessment determine the fitness-for-

purpose of a data set

data retrieval e.g., format

metadata

… to accompany the data

Original source

Data processing

lineage

Data quality

More about metadata

What – the title & description of the dataset.

Why – reasons for the data collection.

When - the dataset was created & updated.

More about metadata (2)Who – the originator and data supplier.

Where - the geographical extent based on lat/long, co-ordinates, geographical names or administrative areas.

How - to obtain more information or order the datasets inc. formats, media access, constraints.

Metadata standards & tools

Dublin Core established some principlesNational standards

e.g. US FGDC, UK NGDF & UK eGMS

ISO 19115ISO 19139

XML implementation schema e.g. UK Geo-Spatial Metadata

Interoperability Initiative (UK Gemini) MetaGenie

Cost : Benefit Analysis

Expensive to generate metadata represent a high level of

abstraction and may need an expert to define

But the benefits are substantial

metadata make it possible to find data sets, and use them effectively

they allow the benefits of investments in data to be realized

Gateways Metadata describe each data set But, how does a user know which

metadata catalogue to search? ‘collection-level’ metadata describe

the contents of entire collections… …meta-metadata

e.g. UK Gigateway, Geography Network

The bigger picture: spatial data infrastructures

National & regional NSDI (US) INSPIRE (EU)

Global GSDI

…a new Global Information Society?

ConclusionsMetadata is important to Document data (good practice) Address heterogeneity

Data & software components Address distribution

Data & software Components

It helps to develop Flexible solutions Evolvable solutions (future-proofing your

investment in data acquisition)