2. www.geodan.nl
The Challenge
> Hundreds of thousands of users
contribute information
> Each individual has his own
intents, purposes,
motivations,knowledge and skill
level, tools
> No moderation and a minimal
imposed data model
> Uneven geographical spread of
contributor efforts
3. www.geodan.nl
The Challenge
> Therefore:
> No uniform lineage
> No consistent levels of:
– Data and metadata completeness
– Positional accuracy
– Temporal accuracy
> How to assess
data quality?
4. www.geodan.nl
Crowd Quality
> A novel approach to assessing quality of
crowdsourced geographic information
> Leveraging user and data dynamics unique to
crowdsourcing:
– User Rating
– Feature version
– Feature age and
persistance
– Spatial Flux
5. www.geodan.nl
Advantages
> No reference dataset required
– All metrics can be derived from the dataset itself
> Appreciative of local variations in quality
unique to crowdsourcing