A brief description from their web site (http://www.uclassify.com):

Our dream is to share hardcore classifier technology with everyone. We recognized that classifiers are mostly present at universities research departments and expensive commercial companies. We want to change that. We want everyone to have the possibility to use a top notch classifier – completely free. We find it enormously exciting to see what happens when a tool for creativity is given to the community. We hope to see all kinds of beyond-our-imagination classifiers and incredible web applications being built around the API.

Earlier I have described the OpenCalais Web Service.

The ecosystem of web services

The NASA Earth Observatory Glossary defines an ecosystem as “any natural unit or entity including living and non-living parts that interact to produce a stable system through cyclic exchange of materials” [NASA]. The concept can be applied to Internet-based applications that function as information-consuming or information producing “organisms” and that interact with each other in an interdependent way through exchange of information.

The IBM web site, on the other hand, defines “web services” as “self-contained, modular, distributed, dynamic applications that can be described, published, located, or invoked over the network to create products, processes, and supply chains.”

As discrete, possibly autonomous “organisms” in an Internet-based information ecosystem, web services-enabled applications expose data and/or service end points in multiple ways including Really Simple Syndication (RSS) feeds, and web services Application Programming Interfaces (APIs) using Simple Object Access Protocol (SOAP), XML Remote Procedure Call (XML-RPC) or REpresentational State Transfer (REST). Aside from the use of XML to embed data in responding to data or process requests, an increasing number of web service applications also provide responses using Javascript Object Notation (JSON). OpenCalais and Alchemy use Resource Description Framework (RDF), an XML-based semantic web format that structures data as triples (subject, predicate, object), to respond to API requests and both perform named entity disambiguation by linking to external knowledge bases (e.g., CIA Factbook, Wikipedia, Freebase). These web service applications may even provide machine learning-based services such as natural language processing (specifically named entity extraction and concept annotation), language detection and translation and text classification. Tools that enable semantic processing of content (not just classification) potentially allow exposing richer knowledge-based content embedded in unstructured data such as news about outbreaks and disasters.

Examples:

1. Structured data feeds: RSS, Keyhole Markup Language (KML), JSON, RDF triples
2. Unstructured data transformation: Dapper, Yahoo Pipes
3. Geocoding Services: Yahoo Maps, Google Maps, Geonames
4. Named Entity Extraction: OpenCalais, Alchemy
5. Concept Annotation: UMLS Knowledge Source Server
6. Visualization: SIMILE Exhibit
7. Text Classification: uClassify
8. Language Detection and Translation: uClassify, Google Translate, Alchemy
9. Text cleaning: Alchemy
10. Entity Disambiguation Using Linked Data: OpenCalais, Alchemy

Major challenges to creating and leveraging a web services ecosystem

Updating multiple interfaces. As these web service APIs are in rapid development keeping track of upgraded APIs to enable compatibility and alignment of agent interfaces is a challenge. However, most web service providers keep their users informed of upgrades or changes through listservs, blogs, social networking media (e.g., Facebook or Twitter). The design and development of self-configuring, self-healing agent interfaces that adapt to changes in web service APIs therefore become important.

Sustainability of API provider. Although many web service API providers are companies that have dual modes for providing services (commercial and free), there are also companies that have disappeared because of lack of a sustainable model. The sustainability model impacts the quality of the service being offered. For example, to distribute data and information through Short Messaging System, a strategy one company implemented is to send short advertisements together with data. If SMS has a 140-character message width and this width is split into two, leaving 70 characters, one would be hard put to make use of the remaining space for message or information distribution.

User and Developer community engagement. A few web service API development projects are in the open source domain. In these web service API development projects, the lack of engaged user and developer communities can hamper product improvements and service quality. In addition, without communities to shepherd different but critical components of a web service project through different stages of maturity may mean components of that project may lag behind in development leading to an incomplete product or service offering. A number of web service API providers have engaged their user and developer communities to collaborate and provide critical feedback and ideas for innovation through “crowd-sourcing” in web service API development projects, open source or not. Through this engagement, we see rapid improvements in the quality of web service APIs and more feature rich service offerings. By engaging the user communities, web services providers are able to gather end-user requirements in real-time and incorporate these requirements within short iteration periods. By engaging the developer community, the project becomes more sustainable such that even if the chief developer moves on, bustling developer and user communities can keep the project going.

Promising developments

When EpiSPIDER began in 2005, there were only a handful of web services available to connect and outsource “business processes” to. Most of the “business process” gaps, like natural language processing and part-of-speech tagging, were filled by developing “in-house” code to implement these processes. There was an indication things would get better when suddenly there were three mapping APIs to use – Google Maps, Yahoo Maps and Microsoft Virtual Earth – since the first EpiSPIDER prototype sported a Scalable Vector Graphics map interface.

Today, EpiSPIDER enjoys the availability and company of a plethora of web services it can leverage (those mentioned above). The use of data exchange standards (XML, RSS, RDF, JSON) have become commonplace in currently available APIs and developers over time have made better sense of how these standards need to come together and enable “interoperability” among different “organisms” of the web services-based information ecosystem. Web services APIs currently in existence and under development herald a new era where previously esoteric processes have now been “commoditized” that one can think of having veritable web services “building blocks” to create information processing pipelines.

And in the current climate where transparency, accountability and data sharing are encouraged, web services are there to make this climate even more valuable by enabling processing of information from distributed data repositories and recombining content from these repositories to come up with a new “whole that is greater than the sum of its parts.”

Nick Zakas offers this article to help users understand what event generates this dialog box and how to address this issue in different browsers (except Chrome).

First, to aid in “noise reduction” brought about by tons of emerging infectious disease data on the web, we implemented bayesian filtering using dbacl, short for digramic bayesian classifier, developed by Laird Breyer. dbacl is implemented as a compiled C application, and therefore works blazingly fast. We are developing a PHP wrapper class to fully harness its benefits in EpiSPIDER’s web environment.

Recognition of location and medical condition entities are two areas of interest for EpiSPIDER and “outsourcing” the ability to extract critical data from unstructured information leverages the emerging, bottom-up, service-oriented architecture on the web.

Although OpenCalais performs on almost any text thrown at it, the following pitfalls were observed for named entity recognition:

1. Using OpenCalais (OC), EpiSPIDER extracted the location entity Buffalo, Indiana, US from the ProMED Mail report with the title “PRO/AH/EDR> Undiagnosed deaths, buffalo – India (Orissa): RFI”.
2. OC did not “disambiguate” between Atlanta, New York, United States and Atlanta,GA, United States.
3. OC georeferencing assigned Norway with lat/long values that are locaed in the Russian heartland.
4. For some unknown reason, it identified West Virginia as part of South Korea.

In spite of these rare glitches, the OpenCalais web service heralds exciting times as we see computing and network power bring down the barriers to an emerging service-oriented architecture out there.

What is event-based surveillance?

As defined by the WHO, event-based surveillance is the organized and rapid capture of information about events that are a potential risk to public health. This information can be rumours and other ad-hoc reports transmitted through formal channels (i.e. established routine reporting systems) and informal channels (i.e. media, health workers and nongovernmental organizations reports), including:

• Events related to the occurrence of disease in humans, such as clustered cases of a disease or syndromes, unusual disease patterns or unexpected deaths as recognized by health workers and other key informants in the country; and
• Events related to potential exposure for humans, such as events related to diseases and deaths in animals, contaminated food products or water, and environmental hazards including chemical and radio-nuclear events [1].

Compared to classic surveillance, event-based surveillance is not based on collecting information about individuals, animals or plants; rather, it is based on reports about who or what is afflicted with disease. These reports can come from many sources, curated or uncurated, and is usually in free text (or unstructured) format.

Web services

An entry in Wikipedia defines web service as “a software system designed to support interoperable machine-to-machine interaction over a network,” such as the Internet [2]. In recent years, news sources such as Reuters have popularized distribution of online content through RSS feeds. RSS stands for Really Simple Syndication. RSS feeds are the most overlooked but widely deployed web service on the Internet today. An O’Reilly web site article highlights this often missed detail in the history of web services[3]. RSS is based on Extended Markup Language (XML) and has a few variants (e.g., version 1, version 2 and 0.92). These feeds impose a structured format for distributing content. Each item in a feed has, at a bare minimum, a title, date when news item was published and a short description.  Many software platforms have developed Application Programming Interfaces (APIs) to extract feed content from online sites. One variant of RSS, called GeoRSS feeds, contains geographic information (latitude and longitude). Currently, a number of public health agencies, including the WHO and European Surveillance Network post content about health-related events (outbreaks) on their sites and also make them available as RSS feeds. The other methods by which web services are made available include:

• Simple Object Access Protocol (SOAP)
• Representational State Transfer (REST)

SOAP and REST are both XML-based information exchange platforms. A majority of the web services support the simpler REST method.

Web services and event-based surveillance

How can web services be used in event-based surveillance? Aside from RSS feeds, we can find quite a number of both health- and nonhealth-related sources that offer web services. Among these are:

• Terminology services
  • Unified Medical Language System Knowledge Source (UMLSKS) server.
• Annotation services
  • OpenCalais
• Visualization services
  • Google Visualization API
  • SIMILE Exhibit
• Information services
  • FUTEF Wikipedia API
• Geolocation services
  • Google Maps
  • Geonames
  • Yahoo Maps
• Data extraction / transformation
  • Dapper (Data mapper)
  • Yahoo Pipes

With these web services, developers can come up with ingenious applications that connect APIs together as a processing pipeline – from harvesting unstructured data, transformation from one format to another, linking with other information sources and visualization.

Web services and beyond

Think about weaving these web services into a coherent architecture that serves a particular (useful and practical) purpose. Beginning with the end in mind, the limit is one’s imagination. The requirement to weave these services together and begin to serve a purpose in a domain such as public health is not trivial if one has to put together natural language processing, information retrieval, semantic web standards and data mining in one networked application. Natural language processing, information retrieval and data mining enable extraction of key words and concepts from unstructured data. Description of unstructured data using semantic web language enables linkage to semantically aligned elements from other sources. A welcome development in this connection is the availability of many open-source software products for a multitude of operating system platforms and programming/scripting languages to fulfill nearly every conceivable task towards building this type of application.

References

[1] Event-based surveillance: http://www.wpro.who.int/NR/rdonlyres/92E766DB-DF19-4F4F-90FD-C80597C0F34F/0/eventbasedsurv.pdf

[2] http://en.wikipedia.org/wiki/Web_services

[3] Appnel T. RSS: The web service we already have. 2003 January 22. URL: http://www.oreillynet.com/xml/blog/2003/01/rss_the_web_service_we_already.html.