Chapter 2 - Personality Assessment, Measurement, and Research Design

PSYC 305
Chapter 2 – Personality assessment, measurement, and research design
Sources of Personality Data
- Most obvious source of information about a person is self-report data (S-data)
 Information a person reveals about themselves
- Individuals may not always provide accurate information for a variety of reasons  e.g., desire to present
themselves in a positive light.

Self-Report Data (S-Data)
- S-data: information a person verbally reveals about themselves
- Self-report data can be obtained through a variety of means
 Interviews that pose questions to a person
 Periodic reports by a person to record events as they happen
 Questionnaire/surveys
o Individuals respond to a series of items that request information about them
o Most commonly used self-report assessment procedure
- Advantages
 Individuals have access to a wealth of information about themselves that is inaccessible to anyone
else  e.g., habitual level of anxiety
 Wealth of information  self-report is an indispensable source of personality data.
 Individuals can report about:
o Feelings, emotions, desires, beliefs, and private experiences
o Self-esteem and perceptions of esteem which others hold them
o Innermost fears and fantasies.
o Immediate and long-term goals.
- Disadvantages
 Self-report measures have limitations and weaknesses.
 For a self-report to work, respondents must be willing and able to answer all questions
 People are not always honest, especially when asked about unconventional experiences
o E.g., unusual desires, socially unacceptable behaviours, or less popular traits.
 Some people may also lack accurate self-knowledge.
 Personality psychologists often use sources of data that do not rely on honesty or insight
o E.g., use of observer/observers.
- Self-report can take a variety of forms
 Range from open-ended “fill in the blank” to forced-choice true-or-false questions.
 Sometimes referred to as unstructured (open-ended) and structured (true or false)
o Unstructured: questions allow people to offer open-ended responses rather than force
them to choose from answers  respondents can answer how they like
o Structured: questions that force people to choose from a limited set of answers provided
 respondents must choose which response best describes them.
- Open-ended self-reports
 Prime example  Twenty Statements Test
 Participant receives a piece of paper that is blank, except for “I am” repeated 20 times
 There is a space after each partial statement  participants asked to finish them
o Participant might write I am a woman; I am 19 years old; I am shy; I am intelligent; I
am someone who likes quiet nights at home; I am introverted; etc.
 Personality instruments that use open-ended formats require coding schemes for classifying
responses they obtain.
- Psychologists must devise a way to score or interpret participant’s open-ended responses.

,  To get an idea of how outgoing an individual is, the psychologist might count how many
statements refer to social characteristics.
- Structured personality questionnaires (response options provided) are more common than open-ended
questionnaires.
 Simplest form of structured self-report involves a series of trait-descriptive adjectives
o E.g., active, ambitious, anxious, arrogant, artistic, generous, greedy, gregarious, open-
minded, manipulative, methodical, and zany.
 Individuals are asked to indicate whether each adjective describes them.
 Simplest format for presenting terms is a checklist (e.g., Adjective Check List  ACL)
o Individuals place a check beside adjectives they feel accurately describes them and
leave items blank that don’t.
 More complex method  request participants to indicate in numerical form the degree to which
each trait term characterizes them
o E.g., on a 7-point rating scale of 1 (least characteristic) to 7 (most characteristic)
o Likert-type scale: common rating scale that provides numbers attached to descriptive
phrases  way for someone to express (with numbers) the degree to which a particular
trait describes them.
- Personality scales  typically involves summing scores on a series of individual rating scales
 E.g., personality scale for activity level might consist of adding up scores from rating scales on
energetic, active, and vigorous.
- Self-report questionnaires
 More common than adjective checklists/scales  include statements
 Widely used self-report inventories  NEO-FFI Personality Inventory and California
Psychological Inventory
- California Psychological Inventory (CPI)
 Participants read each statement and then indicate on an answer sheet whether they agree with
the statement and feel it is true of them or disagree with the statement and feel it is false about
them.
o Example  I enjoy social gatherings to be with people; I looked up to my father as an
ideal man; A person needs to “show off” a little now and then; I have a strong desire to
be a success in the world; I am slow in making up my mind.
- NEO-FFI Personality Inventory
 Participants indicate the degree to which they agree the item describes them, using a 1 to 5 Likert
scale, with 1 as the phrase strongly disagree and 5 with strongly agree.
o Example  I like most people I meet; I laugh easily; I often get disgusted with people I
have to deal with.

Observer-Report Data (O-Data)
- O-data: impressions and evaluations others make of a person with whom they come into contact.
 For every individual, there are dozens of observers who form impressions (friends, family,
colleagues, peers, teachers, etc.)
 Observer-report methods capitalizes on sources and provide tools for gathering information
about a person’s personality.
 Observers may have access to information not attainable through other sources, and multiple
observers can be used to assess each individual.
 A more valid and reliable assessment of personality is achieved when multiple observers are
used.
- Advantages
 Observers may have access to information not attainable through other sources.
o Observers can report about impressions a person makes on others