Because the argument, information, project, etc. on which you are working is only as strong as the evidence you bring to it. Your writing or presentation takes on the "character" of your sources.
If you use unreliable sources, your own paper will be unreliable and unbelievable.
In most cases, you are not an expert. So to be believable to your readers, you must bring to your paper (& other projects) the opinions and research of experts. Such sources are written by the experts themselves or rely on expert opinion/research for their content.
The stronger your evidence, the better your presentation will stand up to critical judgment by your professor. Therefore, selecting high quality information is extremely important.
Source:Beck, Susan. The Good, The Bad & The Ugly: or, Why It’s a Good Idea to Evaluate Web Sources. New Mexico State University. 1997. Revised 2009 version retrieved 12-14-2009.
Accuracy -- is the information reliable and error free?
Is there an editor or someone who verifies/checks the information? Is it peer-reviewed?
Is there adequate documentation: bibliography, footnotes, credits, quotations?
Are the conclusions justified by the information presented?
If you are unable to verify accuracy based on these 3 bulleted items, look outside the source itself (do additional research): Is the information verified in other sources? Do experts agree on the findings?
Authority -- Is the source of the information reputable?
What are the author's qualifications? staff reporter? scholar in field?
How did you find the information? Did you use an index or references from other works?
What type of source is it? Sensationalistic? Popular ? Scholarly?
What is the reputation of the publisher?
If no individual is taking responsibility for the article, who is?
Evaluate the publisher's reputation for guaranteeing accuracy. (If no author is given on a web page, is the sponsor of the page reputable? If the sponsor is also not indicated on the web page, can you determine its origin from the URL and digging deeper into its website)
Objectivity -- Does the information show bias?
What is the purpose of the information? -- Inform? Persuade? Explain? Sway opinion? Advertise?
Does the source show political or cultural biases?
If you are unable to determine objectivity based on the bulleted items above, look outside the source (do more research): Do other sources provide other viewpoints?
Currency - When was the information published? When was the information collected?
Is it current?
Does it reflect the time period about which you are concerned?
Coverage -- Does it provide the evidence or information you need?
Is the audience for which it is intended appropriate for your purposes? (professional, layperson, child, adult?)
Is it suitable for your level of understanding? (too simple, too difficult?)
Is the information in the appropriate format? (print, electronic, video, sound?)
Does it cover the topic(s) you need? Does it provide the main points or concepts you need? Do its major findings add to your understanding? Do they support or refute your original ideas on the topic?
SOURCE: Alexander, Jan and Tate, Marsha Ann. 1996-2005. Evaluating Web Resources. Wolfgram Memorial Library, Widener University. [all quotes below are from the 21 July 2000 version]
Advocacy Web Page "is one sponsored by an organization attempting to influence public opinion (that is, one trying to sell ideas). The URL address of the page frequently ends in .org (organization)."
Business/Marketing Web Page "is one sponsored by a commercial enterprise (usually it is a page trying to promote or sell products). The URL address of the page frequently ends in .com (commercial)."
News Web Page "is one whose primary purpose is to provide extremely current information. The URL address of the page usually ends in .com (commercial)."
Informational Web Page "is one whose purpose is to present factual information. The URL Address frequently ends in .edu or .gov, as many of these pages are sponsored by educational institutions or government agencies."
Personal Web Page "is one published by an individual who may or may not be affiliated with a larger institution. ...[The] URL address of the page may have a variety of endings (e.g. .com, .edu, etc.)...."
Every item you find when searching the Internet must be suspect until you find proof of its reliability. Get in the habit of checking for some key pieces of information when you find a promising article (or other information) on the Web.
Who is the author? -- If no individual is taking responsibility for the article, watch out. If no author is given, dig deeper to find out what the sponsoring organization is. If the article or information is part of a reliable web site -- for example, the Mayo Clinic -- then the information may be trusted even though no author is given.
What are the author's qualifications? -- A medical article written by an M.D. from a reliable medical research facility carries more weight than one written by someone who does not have medical credentials or who claims medical credentials that cannot be verified. Look to see what the sponsoring organization is. If the article or information is part of a web site known to be reliable then the information can be trusted, and any credentials given (e.g., degrees, job title, publications) can be trusted.
What is the author's purpose? -- An article written by an M.D. working for a company selling health food may be more interested in selling a product than in telling the whole story. An author may have a particular political or social agenda and may not be giving you an objective account.
Is there a bibliography? -- An article with a bibliography of good sources carries more weight than an article without a bibliography, because you know who the author's sources are. On the other hand, a veterinary school may provide animal disease information for pet owners that is quite reliable, but not cite sources because it is not intended for a scholarly audience. You would trust the information because it was on the web site of a known and credible veterinary school.
Karl E. Mundt Library, Dakota State University, Madison, South Dakota 57042