Since I began designing for Biodiversity data, I've encountered lot of interesting challenges related to the size of the datasets .
Maybe, one of the hardest challenges is designing a taxonomy browser visualization. The taxonomy browser can represent up to 1.7M names, with nodes with more than 200 childs. That makes it complicate in terms of interaction design and performance.
I will write in a series of post my impressions on different techniques we have been experimenting:
In this first post I'm going to talk about tree list visualizations, but before I get into details, I'd like to talk a little about generic concepts that might be applied to all the visualizations. There is a lot of bibliography about trees out there, but let me introduce here my own "easy" concepts.
When browsing a tree you need to know where you are and what is around you, thats parent and brothers and in general this is called Contextualization. Then you need to be able to find the childs, thats Discovering. All this needs to be easy to do, Usability and UX, and finally must be easy to integrate with the application, Easy integration.
On those terms, the tree list visualization presents some advantages and disadvantages.
- Contextualization: Maybe the list visualization is the most standard way to solve this problem. The tree lists lets the user discover the whole tree by clicking in the different nodes. But the problem is the vertical size that the tree gets when the user deployes a node (This is an integration problem too). When the user will have deployed more than 3 levels, he will have to use the vertical scroll, and probably, this action will make the contextual information (parent nodes and "brothers") out of the visible screen area.
This problem could be solved implementing some variations in the Tree list; We could hide all the nodes not related to the selected child and get more space for view only the important nodes.
-Poor UX : "Discovering biodiversity". We have to involve the users in our play and invite they to discover more and more. I think the Tree Lists are a little boring...we need more action!
- Usability: This visualization is pretty used and the users will understand how it works quickly. On the other hand, I think that in a Tree list is not so easy to find the desired node - the users would have to deploy a lot of nodes, and scroll a lot too, before find their objective. Maybe would be positive for this point to implement a search box. It might depend of the data size.
Conclusion; We've a standard visualization that lets us to implement a Taxonomic browser in a lot of different situations. I think this is not the best solution that we could implement, but its true that we could use this always.