Flashcards in Study Guide 1: Intro to Measurement Deck (19):
when a score represents the answers to a number of questions relevant to a certain construct. Numerous issues complicate the use and evaluation of composite scores.
most often seen in settings in which a decision must be made about a person’s skill level. A fixed predetermined cutoff test score is established, and it is used to sort people into two groups
a type of participant reactivity: some participants may try to change their behaviour to accommodate the researcher, once they figure out the researcher’s purpose.
Sir Francis Galton
(1822-1911) tried to measure the efficacy of prayer. A meteoroloicst, a geneticist, and made important contributions to measurement in both those field. Also conducted Anthropometrics – the measurement of human features such as head size, arm length etc. He is the founding father of modern psychometrics, as he made many conceptual and technical innovations that are the foundations of much psychometric theory and practice. Demoed normal distribution’s utility, the correlation coefficient, and pioneered the use of sampling for the purpose of identifying and treating measurement error.
the behaviours of the same individuals at different points in time
the behaviour of the same individuals at different points in time.
description of attributes or characteristics in terms of numbers
used to compare a person’s test score with scores from a reference sample. Characteristics of the reference sample are thought to be representative of some well-defined population.
Observer or scorer bias
when the researcher might have a vested interest in certain intelligence test score outcomes and as a result, might allow a bias to influence the testing procedures
Add this later.
the act of being measuresd can itself influence the psychological state or process being measured. A person’s reaction may obscure the interpretation of the behaviour that’s being observed.
not time limited. Examinees are expected to answer all the test questions. Scored by counting the number of correct answers made. Test items must range in difficulty if scores on these tests are to be used to discriminate among people with regard to the psychological attribute of interest.
a “systematic procedure for comparing the behaviour of two or more people” – Cronbach (1960). – these tests involve behavioural samples of some kind, that are collected in some systematic way, and their purpose is to compare the behaviours of two or more people. Furr and Bararch add that they could be used to compare the same individual’s performance across time.
the science concerned with evaluating the attributes of psychological tests. Three are of particular interest: the type of data generated by the test, the reliability of the data, and issues concerning the validity of the data.
Sensitivity refers to the ability of a measure to discriminate adequately between meaningful amounts or units of the dimension that is being measured. Thus a scale may be too crude or insensitive.
a type of participant reactivity when a participant may change their behaviour to try to impress the person doing the measurement.
time limited tests. Typically, people who take such a test are not expected to complete the entire test in the allottedtime. They are scored by counting the number of questions answered in the allotted time period, with the assumption that each question will be answered correctly and each of the questions should be of comparable difficulty.
Classical Test Theory
Sometimes referred to as True Score Theory. It is the main focus of this course. Based on: Observed Score = True Score + Error