Lesson 5.1: Credibility

Access Lesson 5. 1 slides here


  1. Ranking is not credibility
  2. Search terms impact the flavor of results
  3. Reading a web address to help assess a page
  4. Using time filtering to help confirm facts

Now that you know so much about finding information, you can start to compare and contrast the pieces of information you uncover. This lesson focuses on checking your facts.

When you search on the Web, you should not just take in something you find and immediately believe it, but actually understand it deeply and see whether or not it is credible. What “credible” means varies a lot from context to context, however.

When you first do a search, you get back a ranked set of results. Just because Google puts a result first does not necessarily give it any credibility. The top spot in the search results means that this is a very highly ranked result with respect to all the functions that Google uses in order to determine if this is a valid, appropriate result for your query. Recall that in lesson 1.3, Matt Cutts said that Google considers over 200 questions in determining this rank order.

Say you submit a query where something comes back that is completely incredible to you. It could be because your search terms appear commonly in a link into that page, or that the page has a lot of content relevant to your query. But that is not exactly the same as credibility. Think of it more as a popularity measure where Google has done a lot of work to try to remove the content that might be spurious or off topic. So, the top pages will match closely with your query topic, but that's not exactly the same as credibility.

Another important thing to keep in mind when you are doing your queries is to think about appropriate terms. Certain terms carry a lot of political and semantic freight with them. If, for example, you do a search for something like [obamacare], it implies a set of perspectives on that topic. So, you have to understand what is going on when you do a particular kind of search.

One of the great things about the fast, iterative nature of Google is that you can find out what those perspectives are very, very quickly. You can dive deeply into the different perspectives on Obamacare, for example, by looking at blogs or news posts or a whole variety of things that are out there. Using Google search allows you to very quickly see all those different points of view.

You could also compare terms to find out about The Falkland Islands in South America. If you use the term [Falklands] you’re gonna get one set of results. If you use the terms [Malvinas], you'll get a different set of results. They refer to the same islands, but one is the English term and the other one is the Argentinian term. Each carries a set of perspectives on whether or not the state owns the islands, or which state owns them, or who should protect them, or what the whole story is behind those islands. So, be aware that the search terms you use may give a perspective that you may not know about and you need to understand.

Credibility is really not just a single simple function. You can do things to help out your search by looking for fact-checking sites. There are a lot of them in association with political topics and in associating with topics that come up a lot in the news. They are incredibly valuable, if only to understand their perspective.

One heuristic Dan often uses is: “Just do one more search."

It is incredible how often people do a quick search, find an answer, and feel content. Just finding a first answer is not really enough. Ideally, you will walk away from this class thinking, "I can do one more search. One more search will get me to a higher degree of credibility in understanding my topics."

Several methods you have learned in previous lessons are useful in checking credibility:

1. Reading the web address

One method to do that is to look inside the web address (URL). In a prior lesson, you explored the idea that a web address is composed of several pieces, but look a little more closely, now.

Consider this fictional web address:


Within this address there is a directory called imperialism, pointing to a document called panamacanal.html. This address is telling you something about the philosophical leanings of the site. You know that this particular document about the Panama Canal, which may have a generic title, such as "The History of Panama," is actually coming from a particular perspective that is signaled by the use of the word “imperialism” in the address.

Pay attention to those things when you are looking at your results. They will often give you a quick first signal about what you will find.

2. Time range

Another technique you can use to sanity check and validate results is checking the time range of a document.

For example, not long ago, this quote got a great bit of play on the Internet because it was attributed to Martin Luther King:

“I mourn the loss of thousands of precious lives, but I will not rejoice in the death of one, not even an enemy.”

--attributed to Dr. Martin Luther King, Jr.

In his blog post, Robert Strohmeyer from PC World points out that Google's range date search limiting trick can be used to determine whether or not Martin Luther King really said that sentence.

Start by searching for the quote [ "I mourn the loss of thousands of precious lives” ].

Figure: Search results for the query [ "I mourn the loss of thousands of precious lives” ].

There are a lot of references to it on the Web.

Next, click Show search tools in the left-hand panel, then the Custom range… link. Leave the from field empty for infinite past, and put 1/1999 in the to field.

If Martin Luther King said something like that before the year 1999, it would certainly show up. Dr. Martin Luther King published a great deal of content during his life. And his speeches have all been transcribed. This is an indication that something fishy is going on. How is it possible that out of all the writings and speeches of Dr. Martin Luther King, this particular phrase never really appeared?

In doing this search, you are using Google's range restriction feature as a mechanism to look back in time. This is a way to start to get a hint that maybe something needs to be looked into a little more deeply. And in truth, it turns out that was an inappropriately attributed quotation from somebody else that got attributed to Martin Luther King. This is one way to find out.

So, remember that there are a number of different kinds of things you can do in order to start to get a sense of the deeper credibility of a resource. The fact that a website appears as number one, number two, or number three in the Google search results page does not necessarily give it factual credibility. It could be very convincing. It could be very well written. But it may not be true. Truth is not exactly the same as appearing high in the web rankings.

With these tools, I think you now have the ability to go more deeply into your content and I urge you to do that and try that on your next set of exercises.

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