Choose your vehicle - navigating the web

Getting timely information from the internet is a little like driving in Sydney. All you want to do is get what you came for and get out again, but it’s all too busy, there are too many options, street directories are always outdated, and there are no friendly faces to give you a hand. In this article we will discuss ways to negotiate the traffic safely.

The dot com companies believed that if you built a good site, people would come back to it time and again. However, internet users behave differently to TV viewers. Rather than going to a particular site for information, people use search engines to find what they are after. So successful search engine skills are the key to grab and run surfing.

First, choose your vehicle. Search engines are of three major types.

Spider

Spider (or WebBot, short for robot) search engines visit a page on the web, recording the title, the words used, and any special hidden information about the page planted by the webmaster. They then follow every link on the page, recording the information on the new pages, and in turn following their links. Spiders therefore collect an enormous amount of information, although they may miss many pages that are not in their link loop and they take some months to return to a page to check if it still exists, or if the information has changed.

Such search engines stand and fall by their ability to calculate the relevance of the sites they present to you. If you are searching for cystic fibrosis, you want sites that are primarily about cystic fibrosis, rather than a page that mentions it in passing. Returning 12,000 irrelevant sites is worse than useless. Different sites have different formulae for calculating the relevance of a page to a request.

Of the spider engines I find that Google (www.Google.com) provides the most relevant results. It calculates the importance of a particular page by counting the number of other pages that link to it.

Directory

The second type of search engine is the directory-sites arranged by subject.
Webmasters submit their sites to the directory, nominating the subject it belongs in. Yahoo (www.yahoo.com) is the most comprehensive of these.

Therefore, to find sites about cystic fibrosis, you go the Yahoo chapter Health > Diseases and Conditions > cystic fibrosis.

Directory engines are less comprehensive than spider engines, but are useful when looking for a particular broad subject.

Directory sites are sometimes likened to the contents of a book, while spider engines are comparable to the index. You would use Yahoo if interested in cystic fibrosis generally, but Google if interested in, say, the use of surfactant in cystic fibrosis.

The third type of search engine is the meta-search engine, which searches a number of other search engines and collates the results. The best of these is Ask Jeeves, at www.askjeeves.com

The division has established a specialised search engine aimed at doctors, which combines these three types: www.nrdgp.org.au/search.html.
When searching, it has its own directory of sites that doctors have previously found useful, and it also searches Google, Yahoo and a number of medical sites. It collates the results in its perceived order of relevancy. When you select a site from the list, it is added to the database, so that the next time a doctor searches for that term it will be higher up the relevancy list.

When you next return to the site, it will ask you to categorise and quickly score the site you last visited. In this way, it will learn and categorise the sites most useful for doctors. I would encourage you to test it out and send me your suggestions at Tony Lembke

Safe driving.