Each graduate of the Master of Library and Information Science program is able to design, query, and evaluate information retrieval systems;
Information retrieval systems store, organize and retrieve documents from directories, indexes or other storage spaces. We use information retrieval systems everyday, but for information professionals, it is a major component in our work. For example, OPAC’s, online databases, digital libraries and web search engines, like Google and YouTube, are different types of information retrieval systems that we come across daily. These different types of information retrieval systems share the same function in retrieving information, but the way they organize and retrieve is different and requires different strategies. Understanding how information retrieval systems are designed and used will help information professionals become effective searchers. Being an effective searcher also requires, that we understand that evaluation is an important tool in improving information retrieval systems. The speed of technological updates and user needs requires that information retrieval systems be updated as well. As information professional information retrieval systems play an important role in discovering and providing access to information.
Design
Information retrieval systems are designed to retrieve records or documents that are relevant to a user’s inquiry, but there are different types of information retrieval systems that are designed for different purposes. For example, databases are designed differently than search engines because databases need to be organized and centralized. Web search engines rely on web crawlers and algorithms, with no centralized organization or hierarchy, so there indexing is different. These affect the number of fields and subfields, the type of indexing required, sorting, formats for display and the availability of other search options. When designing information retrieval systems, designers need to be aware of its intended use and audience to create an information retrieval system to meet these specific needs. When designing it is also important to consider presentation and ease of use. Understanding how information retrieval systems are designed is important for information professionals because we can use and evaluate them more effectively. It is also important for information professionals because advancements in information technology require that we understand the basic foundations of information retrieval.
Query
For information professionals, understanding how information retrieval systems function is important for conducting successful queries. A query is an expression that summarizes an informational need and is an interactive process between the user and information retrieval system. A user inputs a query or search string into a search engine and the information retrieval system searches its collection and ranks the information according to the most useful in descending order. If it is too restrictive nothing comes out and if it is too general the information we are looking for is buried deep within irrelevant results. The process at times is ongoing an sometimes requires modification until the right query is formed. For information professionals, it is important to understand that searching is an ongoing process, and that modification of our search query is part of this process.
While understanding that the search process requires modification, it is just as important to know how to effectively construct search strings the first time around. It saves time and produces results that are more relevant to our search queries. There are several tools and search options that information retrieval systems contain that are important for information professionals to know about. For example, a knowledge of the Boolean operators AND, OR and NOT allows users to impose conditions for search terms that require the addition, exclusion or combination of terms to appear in retrieved records or documents. Proximity and range allow a user to specify the location of terms within a document. Wildcards and truncation search for different variants and spellings of search terms, so that users don’t need to input this information and create long search strings. Many information retrieval systems contain search fields or field limiters, such as subject, author, date, keyword etc. to help users communicate how they want to narrow their searches. For advanced searchers using database codes and prefixes allows precise control over terms than field searches do but requires investigating search options of the information retrieval systems. Controlled vocabulary lists are also important tools to utilize in information retrieval systems. The presence of controlled vocabulary is useful for retrieving results that are precise because keywords are not the most reliable to use. Keywords use different terminology not used across all articles and at the discretion of the indexer, while controlled vocabulary gives us a predetermined list to work with that has been pre-coordinated across all documents controlled vocabulary is useful when trying to figure out terms in a search field or profession you are unfamiliar with.
Searching on the web involves the same process but in a different way. While databases are organized static collections, the web is not a static collection. The web moves and changes so it uses software to constantly search to update its collection. Software like, web crawlers, searches the web for new items, changes, and deletions and compiles this information in a registry that is indexed and searched. Web searches also don’t contain controlled vocabulary so searchers need to think about the terms they use carefully. When searching in a database or in a web search engine, users don’t always understand the difference between the two and how they compile, index and search information. This results in poor or unsuccessful search results when using the same strategies for both. According to Chowdhury (2010), users cannot explain their informational needs in the form of queries, so it is difficult for them to construct search statements (5). As an information professional, it is important for us to know how to construct queries for different types of information retrieval systems because different retrieval systems require different types of search strings and strategies As information professionals we have the background knowledge to help users construct search queries to suit their needs.
Evaluate
Evaluation of information retrieval systems is another important step in improving the design and functions of information retrieval systems. It is important to know how effective the information retrieval system is because we want to improve the relevancy of search results and where the success and failures lie. Information professionals also want to know whether we need to adjust our search strategies, or if there is a better retrieval system to use. One way to evaluate is through user’s experiences with the information retrieval system. This is important because we gain a lot of useful knowledge about user behaviors and preferences that will help make an information retrieval system easier to use. Another way to evaluate is to measure the performance of the information retrieval system. One method is calculating recall and precision percentages. Recall scores relate to the ability of a system to retrieve relevant documents, while precision relates to the ability not to retrieve non-relevant results (Chowdhury, 2010 p. 287). The ability to measure recall and precision is important because it is one way to measure the performance of a system that would be included as part of a bigger evaluation. When evaluating information retrieval systems it is important to look at multiple variables, such as presentation, ease of use, coverage of collection, and response times to avoid error and bias. The information seeking behaviors of users are affected by cultural and technological changes, therefore information retrieval systems need to accommodate these changing needs with repeated evaluations.
Competency Development
In order to develop my knowledge about information retrieval systems and improve my searching skills, several courses have been vital to my education. Libr 202, Information Retrieval, is a foundational course in understanding information retrieval systems and searching techniques. We looked at the principles of information retrieval and their application to information systems and services. We designed a database and evaluated several information retrieval systems. We also looked at the information needs of intended users and used evaluation measures, such as precision and recall. Another course that was important to my understanding of information retrieval systems is Libr 244, Online Searching. In this course the searching techniques learned about in Libr 202, are expanded and explained further with in-depth demonstrations and hands-on assignments. Database content, search language, and syntax are described and we practiced searching techniques in ProQuest Dialog, Web of Science, and LexisNexis. The information and strategies learned from these courses have helped me become a better searcher using OPAC’s at the library I work at. These two courses have been vital to my understandings of information retrieval systems, and have been useful for real-world applications.
Evidence 1: Libr 202 Database Design
For this assignment, I worked with a small group to create a database with twenty records in InMagic DB/Textworks. Our group decided to create a database for an antique toy collection and created a database looking at the needs of toy collectors. We worked collectively to decide what fields and rules were important for our database. We then created structure and content standards for records and fields so that records that are added and recreated are standardized. In Part A, we created a statement of purpose for the database and described our intended user group and their informational needs. When creating databases it is important to know who the intended audience is so that creators can effectively plan and design databases. For our database, this affected our choices in the types of fields and data we wanted to make available. For example, we included a field for the price because collectors are usually interested in the cost of items. We then created rules for the descriptions of our collections, to standardize indexing. Part of the assignment was to create an analysis of our record structure and describe why we picked our attributes and fields. For this part of the assignment, it was my task to analysis our record structure and provide explanations for our choices. An analysis of record structures is important because it explains why the fields we are using are necessary for our database and puts into perspective the choices that are being made. This is useful because if the database needs to be revised at a later date, there are explanations available so that decisions will be made about what needs to be changed. It also serves as a structural map for the creation of other databases that are similar in audience and function. This part of the assignment demonstrates that I can design and analysis databases and use the information from here to design other databases in the future. It is important to know how databases are designed because it will help me improve how I search databases and how I help design databases to suit the needs of users.
Evidence 2: Libr 202 Evaluation of a Library’s Web-Based Catalog
For Libr 202, I evaluated an information retrieval system using the fundamental concepts learned about information retrieval systems. In the essay, I discuss the background of an information retrieval system under evaluation and provide a brief system overview. This is an important step in the evaluation process because information professionals need to understand the intended audience and their needs before we can make decisions about effectiveness and efficiency. I also analyzed indexing mechanisms and search features to understand how the information retrieval system indexes and produces results. I learned that looking at the indexing mechanism of an information retrieval system is another important part of the evaluation process because we need to understand how the system is organizing the information. I also found that search features are important to study because there are many options available in different information retrieval systems that need to be investigated further. Depending on the information retrieval system, it is necessary to become familiar with these types of options to improve our searching strategies. As an information professional, I will be exposed to different types of systems, so I need to have an acute awareness of basic and advanced search options. In the essay, I also discussed search effectiveness using recall and precision measures. This is also another important aspect of the evaluation process because it allows me to test my search results to create scores to compare with moderate levels of performance. According to Chowdhury (2010), moderate levels run at 50-60%, so I had a base to make comparisons with the information retrieval system under study. This part of the assignment demonstrates, how I can calculate performance measures for information retrieval systems to make comparisons with average performance levels. With this information, I was able to construct an evaluation of the system’s performance against other measures, such as usability and design. The information and concepts I have learned about evaluations will help me devise plans to construct evaluations for the systems I work with so that we are working with systems that are meeting our needs. It is important to be working with systems that function to our needs because it slows our workflows and ends up costing us more resources.
Evidence 3: Libr 244 Exercise 1 – ProQuest Dialog Basics
For Libr 244, I completed an assignment that allowed me hands-on experience searching in ProQuest Dialog. The assignment asked a series of question that contained known item and subject item searches. For each question, I planned a search strategy beforehand and then conducted my searches. The pre-planning allowed me to think about the concepts I have learned and review the features that are available with this information retrieval system. This allowed me to construct search terms and search strings to help me save time when using this information retrieval system. As I become more experienced these type of strategies will help me become a better searcher as I experiment with different techniques. Throughout my searching endeavors, I adjusted accordingly until I reached satisfactory results and looked at the content for relevancy. Reaching satisfactory results depends on the needs of the user, so looking at the content for relevancy is an important part of the searching process. In my assignment, I documented search terms, fields and operators used and search strings for the searches conducted. I then analyzed and evaluated the search process and its outcomes. This assignment allowed me to think critically about the searching process using a sophisticated information retrieval system and demonstrates my ability to use searching strategies and techniques for advanced searching inquiries.
Conclusion
Information retrieval systems will continue to improve as evaluations reveal areas needed for improvement. Looking at user needs is an important part in designing information retrieval systems because if they are not meeting the needs of users, we need to find ways to improve them. Part of our responsibilities as an informational professional is to prevent access barriers. The knowledge I have gained about information retrieval systems will help me use them efficiently at the library I currently work for. It is also important to always look for innovative ways to improve information retrieval systems because users needs do change. For example, it is possible to see how the tools of several information retrieval systems are combined to meet the needs of users. For example, there are OPACS that incorporate the traditional features of a catalog while incorporating web-based technologies like, rating systems, hashtags and other web 2.0 technologies. These catalogs are examples of how information retrieval systems are improving the ease of use with the incorporation of different web technologies that users are familiar with.
Resources
Chowdhury, G. G. (2010). Introduction to modern information retrieval. (3rd ed.). London: Facet Publishing.
Assignments
Libr_202_Part_A_Database_Design
Libr_202_Library_Catalog_Evaluation
Libr_244_Ex_1_ProQuest_Dialog_Basics