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Explore Information — The Information Lifecycle

Why does the information lifecycle matter?

Well, it can affect whether or not you'll be able to find any information about a topic!

If your topic is very current, you might only be able to find first-person accounts (interviews or tweets, for example), or newspaper articles. If you need more in-depth analysis, or an expert's considered analysis, though, it might be too soon for anything to be published - those author are busy collecting information and doing their own research - they just haven't had time yet!

Consider: How current does your information need to be? Do you need really up-to-date research? 

What kind of information is likely to have been produced about your topic? Has enough time passed?

A chart showing the steps in the information timeline - event occurs, only eyewitnesses are available. Same day and in the next week, preliminary news reports appear. Scholars begin to publish works within a few months. Within a year or so, books begin to appear. After Multiple Years, Encyclopedia articles will provide broad overviews of events

Primary, Secondary, & Tertiary Sources

Informational sources can be classified roughly into three groups - primary, secondary, and tertiary - that reflect their originality. These groups are defined generally below.

Primary

Primary sources are original, uninterpreted information.
Unedited, firsthand access to words, images, or objects created by persons directly involved in an activity or event or speaking directly for a group. This is information before it has been analyzed, interpreted, commented upon, spun, or repackaged. Depending upon the context, these may include research reports, sales receipts, speeches, e-mails, original artwork, manuscripts, photos, diaries, personal letters, spoken stories/tales/interviews, diplomatic records, etc.

Think of physical evidence or eyewitness testimony in a court trial.

Secondary

Secondary sources interpret, analyze, or summarize.
Commentary upon, or analysis of, events, ideas, or primary sources. Because they are often written significantly after events by parties not directly involved but who have special expertise, they may provide historical context or critical perspectives. Examples are scholarly books, journals, magazines, criticism, interpretations, and so forth.

Think of a lawyer's final summation or jury discussion in a court trial.

Tertiary

Tertiary sources compile, index, or organize sources. 
Sources which analyzed, compiled and digest secondary sources included mostly in abstracts, bibliographies, handbooks, encyclopedias, indexes, chronologies, etc.

Think of an index that lists all the cases heard by this court during the year.

In the humanities and social sciences, primary sources are the direct evidence or first-hand accounts of events without secondary analysis or interpretation. A primary source is a work that was created or written contemporary with the period or subject being studied. Secondary sources analyze or interpret historical events or creative works.

Primary sources

  • Autobiographies
  • Diaries
  • Interviews
  • Letters
  • Original works of art
  • Photographs
  • Speeches
  • Works of literature

A primary source is an original document containing firsthand information about a topic. Different fields of study may use different types of primary sources.

Secondary sources

  • Biographies
  • Dissertations
  • Indexes, abstracts, bibliographies (used to locate a secondary source)
  • Journal articles
  • Book about a primary source

A secondary source contains commentary on or discussion about a primary source. The most important feature of secondary sources is that they offer an interpretation of information gathered from primary sources.

Tertiary sources

  • Dictionaries
  • Encyclopedias
  • Handbooks

A tertiary source presents summaries or condensed versions of materials, usually with references back to the primary and/or secondary sources. They can be a good place to look up facts or get a general overview of a subject, but they rarely contain original material.

Examples

Subject Primary Secondary Tertiary
Art Painting Critical review of the painting Encyclopedia article on the artist
History Civil War diary Book on a Civil War Battle List of battle sites
Literature Novel or poem Essay about themes in the work Biography of the author
Political science Geneva Convention Article about prisoners of war Chronology of treaties

Adapted from lib.vt.edu
 

In the sciences, primary sources are documents written by the person(s) who conducted the original research. For example, a primary source would be a research article where scientists describe their methodology, results, and conclusions about the genetics of tobacco plants. A secondary source would be an article commenting or analyzing the scientists' research on tobacco.

Primary sources

  • Conference proceedings
  • Original research articles
  • Lab notebooks
  • Data sets
  • Patents
  • Technical reports

These sources are where the results of original research are usually first published in the sciences. This makes them the best source of information on cutting edge topics. However the new ideas presented may not be fully refined or validated yet.

Secondary sources

  • Books
  • Review Articles

These sources tend to summarize the existing state of knowledge in a field at the time of publication. Secondary sources are useful places to learn about your topic in depth. They are useful places to find comparisons of different ideas and theories and to see how they may have changed over time.

Tertiary sources

  • Compilations
  • Dictionaries
  • Encyclopedias
  • Textbooks
  • Handbooks

These types of sources present condensed material, generally with references back to the primary and/or secondary literature. They can be a good place to look up data or to get an overview of a subject, but they rarely contain original material.

Examples

Subjects Primary Secondary Tertiary
Agriculture Primary Research article paper on dairy microbiology Review article on the current state of dairy microbiology Encyclopedia article on dairy microbiology
Chemistry Chemical patent Book about organic chemical reactions Handbook of related organic reactions
Physics Conference proceeding on high energy physics A book about the current state of the field of high energy physics Dictionary of high energy physics

modified from lib.vt.edu

Information Lifecycle

Before starting your research, it's good to know how information is produced, where it comes from, and how it changes over time.

The Information Lifecycle is the progression of media coverage of a particular newsworthy event. Knowing about the information cycle will help you to better know what information is available on your topic and better evaluate information sources covering that topic. 

The Day of an Event
Television, Social Media, and the Web

  • The who, what, why, and where of the event
  • Quick, not detailed, regularly updated
  • Authors are journalists, bloggers, social media participants
  • Intended for general audiences

The Day After an Event
Newspapers

  • Explanations and timelines of the event begin to appear
  • More factual information, may include statistics, quotes, photographs, and editorial coverage
  • Authors are journalists
  • Intended for general audiences

The Week or Weeks After an Event
Weekly Popular Magazines and New Magazines

  • Long form stories begin to discuss the impact on society, culture, and public policy
  • More detailed analyses, interviews, and various perspectives emerge
  • Authors range from journalists to essayists, and commentary provided by scholars and experts in the field
  • Intended for a general audience or specific nonprofessional groups

Six Months to a Year or More After an Event
Academic, Scholarly Journals

  • Focused, detailed analysis and theoretical, empirical research
  • Peer-reviewed, ensuring high credibility and accuracy
  • Authors include scholars, researchers, and professionals
  • Intended for an audience of scholars, researchers, and university students

A Year to Years After an Event
Books 

  • In-depth coverage ranging from scholarly in-depth analysis to popular books
  • Authors range from scholars to professionals to journalists
  • Include reference books which provide factual information, overviews, and summaries

Government Reports

  • Reports from federal, state, and local governments
  • Authors include governmental panels, organizations, and committees
  • Often focused on public policy, legislation, and statistical analysis

https://www.library.illinois.edu/ugl/howdoi/informationcycle/

Information Lifecycle

(Source: Digital Literacy, 2010)