Searchguide – BTH English

There are many different ways to find information. If for instance you want to find material for a paper you might start by using a search engine like Google to search the Internet, but there are many other ways to find relevant information.

The choice of search strategy and what information sources you use is governed by your information need. In order perform a good information search you need to make preparations and be as systematic as possible, and in addition use more information sources than Internet search engines. In this part we will deal with some principles of structured information seeking by building a search strategy.

How to prepare your search

Define the problem

The starting point when seeking information is the definition of the search problem. You have made clear what you intend to write about and you have formulated the issues you plan to address.

Search terms and key words

The next step in the process is to choose the search terms or key words that best describe your topic or problem. The search terms are the words that you yourself use to describe the phenomenon and key words can be described as the terms an author has used to describe an article or a book. The choice of search terms may come naturally, but in more difficult cases, you can get help from dictionaries or encyclopedias. When you search a database, you can either use your own search terms or the key words you find in the index of the database. It is vital for the quality of the search result that you have used correct terms. Try to be rich in associations when you are trying to find search terms for a database search. If you can not find any information with one term, perhaps there is another that is more useful.

Language

There may be reasons to consider which language to use when searching. In medicine for example, Latin terms are often used. In computer science, the use of English terminology is common. Furthermore, the document itself may be written in a language that you can not read, even though the reference is in English.

Up-to-dateness

Another important aspect is to establish how old the information could be. In some fields only documents from the last few years will do, whereas in other fields, e.g. history, you can only use primary sources, which may often be several hundred years old.

Scope

Before you begin the actual search, you may also consider how much information you need to collect in order to solve the task. Sometimes you can be overwhelmed by the great amount of irrelevant information. This is especially a risk if you have not defined your problem clearly. On the other hand it might be valuable to start with a wider search and read up on the subject and then narrow the focus. The important thing is not to loose sight of the problem.

Scientific level

Consider what scientific level the information should have. It may not be practical to use a highly specialized thesis if you are just going to write a short introductory paper. On the other hand, that type of material may be vital when you are writing your master’s thesis or dissertation.

Choosing appropriate sources

Formal sources

What sources you use to find the information you need is of course of vital importance. A common distinction is made between formal and informal sources. Formal sources are central in scientific communication and can be said to sources that have been published in some form, e.g. as books, articles, reports, etc. The advantage of these sources is that you can relatively easily establish their quality, plus they are also easy to refer to, durable and accessible through libraries or archives.

Informal sources

Informal sources also have an important role in scientific communication. Examples of such sources may be news groups and blogs on the Internet, seminars and conferences, conversations with colleagues and experts etc. The great advantage of informal sources is that the information is distributed quickly, flexibly and it is often easily accessed. The disadvantage is that the information is not often scholarly reviewed and it may also be momentary and thereby difficult to refer to.

Primary- and secondary sources

Another common distinction is made between primary and secondary sources. Books, articles, dissertations, reports, etc. are examples of primary sources. Secondary sources are aids of different kinds that point to primary sources. Examples of such are bibliographies, reference databases, library catalogues etc. whose purpose is to facilitate the identification of primary sources.

Selecting sources

You should try to choose sources based on your subject area, for instance when choosing a secondary source, such as a reference database. Most often these are constructed for a specific subject area, e.g. Inspec for technology and Medline for medicine. If on the other hand you are searching a library catalogue you will find references to all sorts of subjects, but they offer other techniques for limiting the search result, e.g. subject word searches.

Document type

It is important to have some knowledge of what type of documents you could expect to find in a database. In a reference database such as Inspec, you will find references to documents that could be books, dissertations, articles in scientific journals etc., but in general you will not be able to access the full text of the document from the database. If instead you are searching a database like Summon@BTH, you will find journal articles in full text, i.e. both the reference and the article itself is in the database. If you search the database ebrary whole books are accessed via the computer. You simply need to decide what type of material you need for your assignment.

Searching databases

Choosing the appropriate database

As was stated above, it is vital for a successful search that you choose a suitable database. On the library web page there are guides for finding information resources in the subject areas you can study at BTH. There you will find recommendations for suitable information sources and databases.

Help pages

When you have chosen a database it is important that you study the table of contents and help pages. Unfortunately databases have different search interfaces and search facilities. This means you can not expect to use the search technique you are used to from one database in another. With the information from the help pages you can start using the database efficiently.

Thesaurus and index

One of the most important aids in an advanced database is its thesaurus and index. A thesaurus consists of controlled vocabulary, i.e. words that are chosen deliberately to describe a document. The terms that are used for description in the thesaurus are constant and are used repeatedly by the people who classify the documents in the database. In doing this the accuracy of the database is improved, since documents are always classified with the same words regardless of who is entering the document into the database. Using subject words from a thesaurus gives very relevant results in general. The index consists of key words, i.e. terms that for instance the author has assigned to the document. They are sometimes called unverified subject words. These terms are often very relevant as descriptions of the documents, and as opposed to the thesaurus, they allow a greater variation of terms. The disadvantage of unverified terms is that documents that have very similar content can be described differently depending on who assigns the terms.

Boolean operators

Most databases support searches with different operators. They are called Boolean and proximity operators. You can learn more about them in the part about search technique. When you have finished these preparations it is time to start searching. Analyze the result and possibly refine the search with more subject words or other terms if the ones you had chosen did not give a satisfactory result.

Search history

When you are making several searches in a database it is easy to forget which words you started searching with. In good databases there is often a function where you can see your search history. Base on your previous searches you can often refine the searches by combining them or by combining previous searches with new search terms.

Try out boolean logic:

Watch this power point about search strategy:

Kent Pettersson
2005-06-22