Improve User Experience with Map Search

[karenmajewicz]

The map search could be enhanced to provide more information and a better user experience.

Behavior

• Bounding box relevancy does not sort items by "best fit." (see Support bbox ratio relevancy strategy #324)
• Since the map on the homepage and search results page does not automatically display anything, users generally don't intuit how to use it

Areas to work on

• homepage collection representation
• search result hit representation

[ewlarson]

Design Goal

Improve the Map by allowing it to “talk” about the collection by default
Place points (for clusters) on the leaflet map visualizing the entire result set

B1G Geoportal exploratory branch

• https://github.com/BTAA-Geospatial-Data-Project/geoportal/tree/feature-stream-cluster-prune

Tech Exploration

• Enable CORS in Solr

  • http://opensourceconnections.com/blog/2015/03/26/going-cross-origin-with-solr/
  • Want to stream data directly from Solr cross-domain
  • IMPORTANT - Would need to restrict domains and HTTP verbs in production
  • Probably proxy it via Apache/webserver instead

• Use Solr’s /export handler

  • https://lucene.apache.org/solr/guide/6_6/exporting-result-sets.html
  • This request handler streams JSON results back
  • The /export handler needs docValues for any field it will stream

• Update GBL schema

  • add a dynamic field type “_sdv" (single value string with docValues)

• Re-index data to store docValues

  • https://gist.github.com/ewlarson/10e66a31cdb31a29cae15961b745eb0d
  • Convert solr_geom to centroid_sdv
  • Copy our doc identifier (uuid) to uuid_sdv
  • Copy doc dc_title_s to dc_title_sdv

• Use Oboe.js (a JSON stream parser)

  • http://oboejs.com/
  • Requires CORS enabled at endpoint
  • SAX parses the JSON result stream
  • Creates markers with a popup for each doc
  • When stream is complete, renders marker layer

• Use PruneCluster

  • https://github.com/SINTEF-9012/PruneCluster
  • Significantly faster than leaflet.markercluster
  • ~6,500 docs renders via PruneCluster (sub 1s consistently)
  • ~6,500 docs renders via leaflet.markercluster (~3-5s)

Homepage — should just cache values for the entire collection
Search Results — need to tie into search query and redirect from /select to /export

[hackartisan]

@sdellis just led some usability testing at Princeton and we're hoping to do some local design work on this same issue. I thought it might be helpful to share some of our recent insights.

At Princeton we display pins on our map with result sets in an attempt to achieve this goal of having the map "talk" about the collection / results. In recent testing these pins were interpreted as points, rather than representative of an area. As a result we are considering moving to bounding boxes for clarity.

Most of our testers relied on either the results set or the map view, and we'd like to integrate the two screen areas better so they are useful in conversation with one another.

Another observation we had was that participants would see just 10 pins in the map (for the 10 results shown), but not realize there were 400 results in the search results set. However this may be partly due to the layout of our results page, which is quite different from the default geoblacklight layout.

A final source of confusion has been that even if I set the bounding box facet by selecting a map area, as I page through results the map zooms out more and more. I believe this behavior is to accommodate the larger and larger bounding boxes of the search result items, but we may want to consider whether we can either adjust this behavior or make it clear that the selected search area is being respected.

[kgjenkins]

A while back, I experimented with an interface that would show the bboxes of all the search results, and it was tricky to come up with a display style that worked well regardless of the number of search results, especially if you want to use fill opacity to let results "pile up" where there is a lot of overlap.

I ended up using a display style with no fill and a very thin stroke, but using a semi-transparent fill when hovering over a result list item. But I'm still not quite satisfied with the way it looks (and please ignore the fact that the highlight colors don't quite match...)

[ewlarson]

Solr Heatmap Faceting was another option Jack had investigated: https://twitter.com/mejackreed/status/596427986942963712?s=20&t=hIRcA6JP0HJh6M5021yi9w

https://github.com/mejackreed/leaflet-solr-heatmap

[eliotjordan]

We decided at the 2/23/2022 Sprint standup that we are going to discuss this at an upcoming community meeting.
@karenmajewicz - For your records.

[karenmajewicz]

Here are notes from our April 2022 meeting:

• do search results always match the map? Incorrect boxes in the metadata cause problems. Is the spatial algorithm boosting working well enough?
• users get confused when the zoom level changes as they page through
• can the geolocation search be part of defalt GBL?

[karenmajewicz]

Here is a slightly different approach to a map search. At the Blacklight Summit, I saw a presentation about Digital Commonwealth by @ebenenglish. They have a Blacklight site with the blacklight-maps plugin. Users can browse the map and select points representing places. This takes the user to all items tagged with that place.

[karenmajewicz]

I am seeing a few different ways that the spatial search is shown as a removable facet value. These are pretty subtle, but might have an impact on the user.

1. Default behavior

Whenever a user moves the map, a Bounding Box value shows up that will change and can be removed.

---

2. Customization with the text "Current Map View" (Princeton)

When a user moves the map, the same behavior occurs, but the label always says Current Map View instead.

---

3. Customization where removable Bounding Box value does not show up unless another facet value has been selected (BTAA)

We recently updated the BTAA Geoportal's layout for the search results page. We (unintentionally?) introduced a new behavior where the Bounding Box value doesn't show up until a user selects another facet.

When another facet is selected, the Bounding Box value appears like the Default

---

Are there other customizations out there with a different way of showing how the current map view is affecting the search? I have seen that sometimes users don't notice that they have facets/bounding boxes selected and don't understand why their results are so limited.

[RyanMattke]

Playing around with the map today I noticed that if I zoom to a place, but then click a facet, the map zooms out to (presumably) include the area covered by all items in that facet (or at least the first 10)? I would think it would be more useful to have the map area override that?

[karenmajewicz]

I have been thinking about this as well - how should the facets correspond with the map? If the map area overrides the facets, how many items would it filter? For example, if you have the default of 10 items per page selected, should the facets only display those 10? That would render the facets much less useful, I think?

This gets back to what Princeton was presenting on yesterday - is the map itself a facet or is it an entirely different search?

I wonder how this would work with how UT has their map set up - where a user must explicitly perform a new search after they move the map.

[kgjenkins]

It seems like there are three ways the current map bounds could be used in a search (or a click on a facet value):

1. Strictly limit results to those that intersect the map extent
2. Boost results based on overlap with the map extent
3. Ignore the map extent

I think it might be okay to narrow that down to just two options (1 and 3)

The big question is how best to offer the choice to users. My initial thought was to have a checkbox near the search box, but that option should also apply to clicks on facet values, which may be further down the page. So perhaps on/above the map would be the best place for a checkbox with text something like "limit search/facet results to current map extent" (needs wordsmithing...) Although I can already imagine that some people will expect that checking the box will instantaneously limit the results (rather than waiting until the next click on the search button or facet value) but that should be possible too.

[kgjenkins]

Another thought: if a bbox is used in a search, would it be helpful to show that bbox on the results map?

[kgjenkins]

Another map-search issue: #985