Introduction to Psychological Testing
Lisa Bueno
University of Phoenix
PSY/475
Psychological Testing and Measurements
Pamela Stewart, M.S.
February 8, 2012

Introduction to Psychological Testing
Define “Test” The word test as defined by the Oxford English Dictionary is, “a cup used for smelting gold or silver ore” (Hogan, 2007, p. 38). Imagining what testing meant for Chaucer in the mid 1300s could be associated with an image of pure data, (perhaps gold or silver) captured and additional data was irrelevant. The Standards for Educational and Psychological Tests defines test as, “An evaluative device or procedure in which a sample of an examinee’s behavior in a specified domain is obtained and subsequently evaluated and scored using a standardized process” (Hogan, 2007, p. 38). In addition, Anastasi and Cronbach define test as “an objective and standardized measure of a sample behavior” and “there is no fully satisfactory definition” respectively (Hogan, 2007, p. 39). Essentially, Hogan (2007) gathered the test definitions and identified six critical elements: device or procedure, gather information, behavior or cognitive processes, sample, standardized and quantified. “A test is a standardized process or device that yields information about a sample or behavior or cognitive processes in a quantified manner” (Hogan, 2007, p. 41). However concise this definition may seem, in order to further understand psychological testing one must uncover the basics, identify the major categories, and compare and contrast validity and reliability as it associates to psychology.

Major Categories of Tests Administering tests in several structured approaches involve analyzing information. Ideally, they enable researchers to touch on every possible outcome. Discussing the major categorizes, users and uses of tests will give one a gradual understanding of psychological testing purposes. Although these major categorizes may seem to pose as the other often making it difficult to distinguish each one, they each offer further understanding to this aspect of psychology. Psychological testing measures have several basic assumptions that are foundational. First, there are traits or characteristics that essentially portray an individual, but importantly the value lies in the differences of each individual in a quantifiable and measurable aspect (Hogan, 2007, p. 15). Second, although, differences are a common variable, the traits and characteristics must remain somewhat continuous minimizing fluctuation so the test data can be used (Hogan, 2007, p. 16). The last assumption relates to the observable behavior an examiner witnesses in order to measure or quantify the behaviors. Another way to classify psychological tests are through several categories of tests. The first test category encompasses mental abilities-testing, both individuals or groups, which evaluate sight, creative processes, spatial and memory capabilities (Hogan, 2007, p. 5). The second is an achievement test directly pinpointing an individual’s knowledge or skills level for specific tasks. Achievement tests are identifiable in the form of certificates, degrees, licensing, batteries, and government sponsored programs (Hogan, 2007, p. 7). The third test is a compilation of a variety of evaluated test based on true-false responses to yield data about human personality known as objective personality test, projective techniques and other miscellaneous methods (Hogan, 2007, p. 7-8). The other two categories focus on evaluating interests and attitudes, along with neuropsychology, through the use of vocational attentiveness measures and tests of brain functioning, respectively. The second most important aspect to psychological testing is the uses and users for these tests. The first category of tests apply to intelligence and objective personality tests for clinical, academic, individual counseling, employment, research, and neuropsychology facilitation (Hogan, 2007, p. 10-14). In clinical use, the psychologist attempts to assist in identifying the mildness or severity of an individual’s mental stability and assist in treating the problem. In academic settings, achievement tests determine the level of learning students have attained. The third method employers and military services assess individuals placement in certain positions through ability and personality tests. The last method encompasses the use of an array of test methods, ranging from dependent variables in experiments, describing samples or research on the tests themselves (Hogan, 2007, p. 14).

Compare and Contrast: Reliabilities and Validities Affects on Psychological Testing Reliability “...deals only with the consistency of the measure, regardless of exactly what it is measuring” (Hogan, 2007, p. 112). Dimitrov (2010), suggests that reliability is not concerned with constant errors of a trait being measured, but in the unsystematic errors or variations in rating from examiners or instruments being used in a test. Validity is “...the extent to which a test measures what it purports to measure” (Hogan, 2007, p. 156). Validity has interests in the distinct purpose of the test. Validity ensures that tests are administered in the manner, intended to evaluate and measure constructs. Friberg (2010) reports that if these test methods used are for anything other than their intended purposes, validity will suffer producing low results. Summing up the two concepts, one can say that reliability equals consistency of annotating scores and the use of measuring devices, whereas, validity entails the proper use of tests, measurement, and purpose. A valid test must be reliable; however, a test can be reliable without producing valid results because of its application.

Conclusion In conclusion, assumptions allow for the interpretation of psychological tests-abilities, achievements, interests and attitudes, personality, and neuropsychological-to measure traits and characteristic constructs. Tests administered in wide ranging clinical, academic, employment, neuropsychological, and research settings. Reliability refers to the unsystematic errors, rather than the constant errors that occur rendering a test far too erratic. Validity ensures that examiners use tests the way intended to produce applicable data for a specific purposes when measuring constructs and taking score.
References
Dimitrov, D. M. (2010). Contemporary Treatment of Reliability and Validity in Educational Assessment. Mid-Western Educational Researcher, 23(1), 23-28.
Friberg, J. C. (2010). Considerations for Test Selection: How Do Validity and Reliability Impact Diagnostic Decisions?. Child Language Teaching And Therapy, 26(1), 77-92.
Hogan, T. P. (2007). Psychological Testing: A Practical Introduction (2nd ed.). Hoboken, NJ: John Wiley & Sons, Inc..