11 Personality and intelligence assessment 1: Basic concepts in measurement Flashcards
What is differential psychology (aka the individual differences approach)?
The division of psychology that seeks to understand and establish the psychological dimensions that apply to everyone, yet allow for differences between individuals.
Are there any overt psychological attributes?
No, they’re all hidden. Shhhh…
What is sampling?
The process of selecting some part (sample) of a target population in order to estimate some characteristics of interest in that population
What is the paradox of sampling (Kaplan, 1964)?
Only way to know representativeness of sample is to know prevalence of depression, say, in population, but if you knew that you wouldn’t need the sample
What is biasedness in a sample?
The degree of error in a sample, which can produce over- or under-estimates of population values
What percentage of psychological tests are run on psychology students?
Approximately 68%.
What is instability in a sample?
The degree of psychological homogeneity within members of population. Eg. In Christian societies test scores differ before and after Christmas
What is psychological measurement?
The process of assigning numbers to a person in such a way that some attributes of the person are faithfully reflected by some properties of these numbers.
What is a construct?
A construct is an explanatory variable that is not directly observable, such as intelligence or motivation.
What is a nominal scale?
A scale on which an attribute is given an ARBITRARY numerical value, such as 0 - No; 1 - Yes
What are dichtomous/polytomous scales?
Dichotomous –0 - No; 1 - Yes
Polytomous –0 - No; 1 - Yes; 2 - Maybe; 3 - Not sure
What is an ordinal scale?
A scale on which an attribute is rank-ordered and a numerical value is assigned to each rank
What characterises the distance between ranks in an ordinal scale?
The distances are meaningless.
What is an un/balanced ordinal scale?
Balanced ordinal scale –has a neutral scale point in the middle. E.g. 1. Hate 2. Dislike 3. Neutral 4. Like 5. Love
Unbalanced ordinal scale – either has no neutral point or that point is not in the middle. E.g. 1. Abhor 2. Hate 3. Dislike 4. Don’t like much
What kind of scale is a social distance scale?
Ordinal; unbalanced
What’s the distinction between a Likert scale and a Likert-type scale?
Only a Likert scale has 5 points (degrees of agreement). Any other number -> Likert-type scale
What is an interval scale?
A scale on which the points have equal distances but no true zero (eg. temperature). Not common in personality psychometrics.
What is a ratio scale?
Ratios between numbers assigned to a person correspond to ratios between the measured attribute in that person. (Eg. reaction time)
What are population norms (normative scores)?
Norms are standardised scores that are assumed to indicate the behaviour (distribution) of an attribute in a particular (normative) group or population.
What is a T-score?
A standard score that sets the mean to fifty and standard deviation to ten.
How do Cronbach and Meehl (1955) very usefully define a hypothetical construct?
Cronbach and Meehl (1955) define a hypothetical construct as a concept for which there is not a single observable referent, which cannot be directly observed, and for which there exist multiple referents, but none all-inclusive. For example, according to Cronbach and Meehl a fish is not a hypothetical construct because, despite variation in species and varieties of fish, there is an agreed upon definition for a fish with specific characteristics that distinguish a fish from a bird. Furthermore, a fish can be directly observed. On the other hand a hypothetical construct has no single referent; rather, hypothetical constructs consist of groups of functionally related behaviors, attitudes, processes, and experiences. Instead of seeing intelligence, love, or fear we see indicators or manifestations of what we have agreed to call intelligence, love, or fear.
