The Handy Psychology Answer Book. Lisa J. Cohen
Чтение книги онлайн.
Читать онлайн книгу The Handy Psychology Answer Book - Lisa J. Cohen страница 35
Название: The Handy Psychology Answer Book
Автор: Lisa J. Cohen
Издательство: Ingram
Жанр: Общая психология
Серия: The Handy Answer Book Series
isbn: 9781578595990
isbn:
What are the critical concepts one needs to know when interpreting the results of a study?
We trust the scientific method to give us reliable knowledge. Nevertheless, research should never be taken at face value. There are many ways a study can be biased and it is extremely important to be able to interpret the results of a study critically. The issue of validity is of particular importance. Are the results valid or is the study flawed to the extent that the conclusions are not supported by the data? Internal validity refers to the integrity of the study methods. Is there a fatal flaw that is intrinsic to the design of the study? For example, a study comparing the effectiveness of two drugs used one drug that had passed its expiration date. In this case, drug B may be less effective than drug A simply because it passed its expiration date. External validity refers to the extent to which the results can be applied to a larger population. A study of attitudes toward religion that only includes atheists will have limited external validity. It may be an accurate measure of the subjects’ religious beliefs but the study would not tell us much about non-atheists. In general, internal validity is more important than external validity.
PSYCHOLOGICAL TESTS
What role do psychological tests play in the science of psychology?
Psychological tests are the bread and butter—the currency—of psychological science. Research in psychology depends upon the measurement of psychological traits, which can only be accomplished with psychological tests. Nonetheless, psychological traits are inherently difficult to assess. They are not concrete objects that are obviously measured, like the number of green peas or the height of a giraffe. They are abstract and intangible traits like love or happiness or self-esteem that can neither be seen, touched, nor counted and may be interpreted differently by different people. Therefore a critical part of psychological research involves the construction of tests that can measure psychological traits in a systematic and reliable way.
What are the different kinds of tests?
There are many forms of psychological tests, all of which offer both advantages and disadvantages. Perhaps the most common form of test is a self-report questionnaire.
A self-report questionnaire is a paper and pencil test on which the subject answers a series of questions about one or more psychological traits. These tests are quick and easy to develop, administer, and score, but they are limited by the possibility of inaccuracies in the subject’s self-report.
Clinician-administered questionnaires are also paper and pencil tests but the clinician asks the subject the questions. These questionnaires allow the clinician to make the final scoring decision based on the subject’s responses to each question.
Interviews, like questionnaires, involve a series of questions administered to the subject, but the interviewer has room to follow up each question with verbal probes to obtain more information or clarify responses. The interviewer has more leeway to modify the questions or add new questions than on paper and pencil questionnaires.
Projective tests, like the thematic apperception test (TAT) or the Rorschach, ask the subject to complete a task (e.g., to tell a story based on a picture), which is intended to reveal characteristic ways of thinking, feeling, and behaving. The subject, however, is unaware of the information being revealed.
In cognitive tests, the subject completes various tasks that involve intellectual skills, like memorizing a list of words or arranging blocks to match a pattern.
Sensory or motor tasks likewise measure sensory skills, such as sensitivity to touch, or motor skills such as visual-motor coordination.
Tests in these last three categories are often called objective tests because they involve the assessment of objective behavior.
How are tests and measurements developed?
A good deal of work goes into test construction. First, the construct must be defined. What exactly are you trying to measure? Then, taking the most typical case of a self-report questionnaire, the items must be selected. Next, the test must be administered to several samples of people to prove that it is a consistent and reliable measure of the construct it is intended to measure. Two critical concepts in test construction are reliability and validity.
What are some examples of test questions that measure emotional or behavioral traits?
The two excerpts listed below give sample items from a psychological test measuring various emotional and behavioral traits. The first group of questions measures anger regulation and the second group of questions measures sustained initiative. The questions can either be read aloud by the examiner in an interview format or given to the subject to fill out as a self-report questionnaire. The answers are translated into numbers, which can then be added together to form a total score.
How frequently have any of the statements listed below been true for you in the past five years?
____ Sometimes I can be really irritable and other times nothing rattles me.
____ There are times when the least little thing makes me furious.
____ I can be really furious about something and then suddenly feel calm and back to normal.
____ I hold onto a grudge for a long time.
____ When I’m angry I cannot easily control my temper.
Some people have a difficult time getting themselves to do things they either should do or would like to do. Over the past five years, how frequently have any of the following statements applied to you?
____ I’ve had a hard time getting around to things I have to do.
____ I’ve had a hard time finishing things I’ve started to do.
____ Although I’m motivated and excited when I start a project (job, hobby, school), I get distracted and bored easily.
____ I give up on things when I get frustrated or bored.
____ I arrive at work more than half an hour late.
____ I arrive at work more than an hour late.
What does it mean to say a test is reliable?
The reliability of a test refers to its ability to measure a given trait consistently. If the outcome of a measure varies each time it is applied, the measure is not reliable. There are several forms of reliability, depending on the format and purpose of the test. Inter-item consistency means that the individual items of a test are inter-correlated, or they are well related to each other. This form of reliability is used with questionnaires in which multiple items are used to rate one trait. Test-retest reliability measures how well an initial administration of a test correlates with a repeated administration. This is only useful if the trait measured is unlikely to change much over time. Inter-rater reliability is used with semi-structured questionnaires and other instruments in which the rater СКАЧАТЬ