Why Develop a New Test?
meet the needs of a special group of test takers
sample behaviours from a newly defined test domain
improve the accuracy of test scores for their intended purpose
Tests need to be revised
First Four Steps
Defining the test universe, audience, and purpose
Developing a test plan Composing the test items Writing the administration instructions
Continued Steps of Test ConstructionDiagram of Test Construction (p. 234)
Constructing Scales Piloting the Test Standardizing the Test Collecting Norms Validation & Reliability Studies Manual Writing Test Revision
Defining the Test Universe, Audience, & Purpose
Defining the test universe. – prepare a working definition of the
construct– locate studies that explain the construct– locate current measures of the construct
Defining the Test Universe, Audience, & Purpose
Defining the target audience. – make a list of characteristics of persons
who will take the test--particularly those characteristics that will affect how test takers will respond to the test questions (e.g., reading level, disabilities, honesty, language)
Defining the Test Universe, Audience, & Purpose
Defining the purpose.– includes not only what the test will
measure, but also how scores will be used– e.g., will scores be used to compare test
takers (normative approach) or to indicate achievement (criterion approach)?
– e.g., will scores be used to test a theory or to provide information about an individual?
Developing a Test Plan
A test plan includes a definition of the construct, the content to be measured (test domain), the format for the questions, and how the test will be administered and scored
Defining the Construct Define construct after reviewing
literature about the construct and any available measures
Operationalize in terms of observable and measurable behaviours
Provides boundaries for the test domain (what should and shouldn’t be included)
Specify approximate number of items needed
Choosing the Test Format Test format refers to the type of
questions the test will contain (usually one format per test for ease of test takers and scoring)
Test formats have two elements:– stimulus (e.g., a question or phrase)– mechanism for response (e.g., multiple
choice, true-false). May be objective or subjective test format
Composing the Test Items
test items are the stimuli presented to the test taker (may or may not take the form of questions)
the form chosen depends on decisions made in the test plan (e.g., purpose, audience, method of administration, scoring)
Test Types Structured Response
– Multiple Choice– True False, Forced Choice– Likert Scales
Free Response– Essay, Short Answer– Interview Questions– Fill in the Blank– Projective Techniques
Multiple Choice Multiple choice most common in educational
testing (and also some personality and employment testing)– consists of a stem and a number of responses--
should only be one right answer– the wrong answers are called distractors because
they may appear correct--should be realistic enough to appeal to uninformed test taker
– easy scoring but downside is that test takers can get some correct by guessing
Multiple Choice Pros
more answer options (4-5) reduce the chance of guessing that an item is correct
many items can aid in student comparison and reduce ambiguity, increase reliability
Cons measures narrow facets of performance reading time increased with more answers transparent clues (e.g., verb tenses or letter uses “a”
or “an”) may encourage guessing difficult to write four or five reasonable choices takes more time to write questions
True/False
True/False is also used in educational testing and some personality testing– in educational testing the test taker can
again gain some advantage by guessing
True/False (cont.) Ideally a true/false question should be
constructed so that an incorrect response indicates something about the student's misunderstanding of the learning objective.
This may be a difficult task, especially when constructing a true statement.
Forced Choice Items
Forced-Choice is similar to multiple-choice but is used in personality and attitude tests (e.g., MBTI)– test taker must choose between unrelated but
equally acceptable responses
Forced Choice Items(cont.)
Example
Place an “X” in the space to the left of the work that of the word in each pair that best describes your personality.
1. ____ Sunny 2. ____ Outgoing
____ Friendly ____ Loyal
Likert Scales
Likert scales are usually reliable and highly popular (e.g., personality and attitude tests)– item is presented with an array of response
options (e.g., 1 to 5 or 1 to 7 scale), usually on an agree/disagree or approve/disapprove continuum
Test Types
Structured Response– Advantages
Great Breadth Quick Scoring
– Disadvantages Limited Depth Difficult to assess higher levels of skills Guessing/Memorization vs. Knowledge
Subjective Items subjective items are less easily scored
but provide the test taker with fewer cues and open wider areas for response--often used in education– essay questions - responses can vary in
breadth and depth and scorer must determine to what extent the response is correct (often by examining match with predetermined correct response)
Essay Questions Provide a freedom on response that
facilitates assessing higher cognitive behaviors (e.g., analysis and evaluation)
Allows respondent to focus on what they have learned and does not limit them to specific questions
Interview Questions– interview questions are often used in organizational
settings--interviewer decides what is a good or poor answer
test plan should be based on knowledge, skills, abilities and other characteristics required to perform the job
Information can be obtained from a job description, job analysis, current job incumbent
Projective Techniques
Projective techniques are often employed in clinical settings– uses a highly ambiguous stimulus to elicit
an unstructured response (i.e., the test taker “projects” his or her perception and perspective onto a neutral stimulus)
– variety of stimuli (e.g., pictures, words) and responses may be verbal or drawing pictures
Sentence Completion Sentence-Completion format presents an
incomplete sentence that the test taker completes (e.g., “I feel happiest when …)
subjective tests are at risk for judgment error and inter-rater reliability is therefore of particular importance--scoring keys and training important
Test Types
Subjective Items – Advantages
Can Test Higher Cognitive skills Encourages organize/develop thoughts
– Disadvantages Difficult to Grade Judgement error (e.g., interrater reliability) Requires Advance - Objective Scoring Key
Writing Good Items Basis building block of test construction Little attention given to writing items an art that requires originality, creativity, combined with
knowledge of test domain and good item writing practices not all items will perform as expected--may be too easy or
difficult, may be misinterpreted, etc. rule of thumb to write at least twice as many items as you
expect to use Broad vs. Narrow items
Writing Good Items (cont.)
Suggestions:– identify item topics by consulting test plan
(increases content validity)– ensure that each item presents a central
idea or problem– write items drawn only from testing
universe– write each item in clear and direct manner
Writing Good Items (cont..)
Suggestions:– use vocabulary and language appropriate for
the target audience (e.g., age, culture)– take into account sexist or racist language
(e.g., mailman, fireman)– make all items independent (e.g.,one question
per question)– ask an expert to review items to reduce
ambiguity and inaccuracy
Writing Administration Instructions
specify the testing environment to decrease variation or error in test scores
should address:– group or individual administration– requirements for location (e.g., quiet)– required equipment– time limits or approximate completion time– script for administrator and answers to questions
test takers may ask
Specifying Administration and Scoring Methods
determine such things as how test will be administered (e.g., orally, written, computer--individually or in groups)
method of scoring, but also whether scored by hand by test administrator, or accompanied by scoring software, or sent to test publisher for scoring
Scoring MethodsCumulative model: most common
– assumes that the more a test taker responds in a particular fashion the more he/she has of the attribute being measured (e.g., more “correct” answers, or endorses higher numbers on a Likert scale)
– correct responses or responses on Likert scale are summed
– yields interval data that can be interpreted with reference to norms
Scoring Methods (cont.)
Categorical model: place test takers in a group
– e.g., a particular pattern of responses may suggest diagnosis of a certain psychological disorder
– typically yields nominal data because it places test takers in categories
Scoring Methods (cont…) Ipsative model: test takers scores are not compared to that of
other test takers but rather compare the scores on various scales WITHIN the test taker (Which scores are high & low)
– e.g., a test taker may complete a measure of interpersonal problems of various types and the test administrator may want to determine which of the types the test taker feels is most problematic for him or her
Cumulative model may be combined with categorical or ipsative model
Response Bias In preparing an item review, each question can
be evaluated from two perspectives: Is the item fair? Is the item biased?
Tests are subject to error and one form comes from the test takers
Response Sets/Styles Are patterns of responding that result in misleading
information and limit the accuracy and usefulness of the test scores
Reasons for misleading information
1. Information requested is too personal
2. Distort their responses
3. Answer items carelessly
4. May feel coerced into completing the test
Response Style
– People always agree (acquiescence) or disagree (criticalness) with statements without attending to the actual content
– Usually, when items are ambiguous
Solution: use both positively- and negatively-keyed items
Social Desirability
Some test takers choose socially acceptable answers or present themselves in a favourable light
People often do not attend as much to the trait being measured as to the social acceptability of the statement
This represents unwanted variance
Social Desirability (cont.)
Example items:
– Friends would call me spontaneous.
– People I know can count on me to finish what I start.
– I would rather work in a group than by myself.
– I often get stressed-out in many situations.
Faking
Faking -- some test takers may respond in a particular way to cause a desired outcome
– may “fake good” (e.g., in employment settings) to create a favourable impression
– may “fake bad” (e.g., in clinical or forensic settings) as a cry for help or to appear mentally disturbed
– may use some subtle questions that are difficult to fake because they aren’t clearly face valid
“Faking Bad”– People try to look worse than they really are
Common problem in clinical settings
– Reasons: Cry for help Want to plea insanity in court Want to avoid draft into military Want to show psychological damage
– Most people who fake bad overdo it
Impression Management
– Mitigating IM:
Use positive and negative impression scales (endorsed by 10% of the population)
Use lie scales to “flag” those who score high (e.g., “I get angry sometime”).
Inconsistency scales (e.g., two different responses to two similar questions)
(Use multiple assessment methods (other than self-report)
Random Responding
Random responding may occur when test takers are unwilling or unable to respond accurately.
– likely to occur when test taker lacks the skills (e.g., reading), does not want to be evaluated, or lacks attention to the task
– try to detect by embedding a scale that tends to yield clear results from vast majority such that a different result suggests the test taker wasn’t cooperating
Random Responding– Detection:
Duplicate items:
“I love my mother.”
“I hate my mother.”
Infrequency scales:
“I’ve never had hair on my head.”
“I have not seen a car in 10 years.”
Random Responding– May occur for several reasons:
People are not motivated to participate Reading or language difficulties Do not understand instructions / item content Too confused or disturbed to respond
appropriately
Piloting and Revising Tests can’t assume the test will perform as
expected pilot test scientifically investigates the
test’s reliability and validity administer test to sample from target
audience analyze data and revise test to fix any
problems uncovered--many aspects to consider
Setting Up the Pilot Test
test situation should match actual circumstances in which test will be used (e.g., in sample characteristics, setting)
developers must follow the American Psychological Association’s codes of ethics (e.g., strict rules of confidentiality and publish only aggregate results)
Conducting the Pilot Test
depth and breadth depends on the size and complexity of the target audience
adhere strictly to test procedures outlined in test administration instructions
generally require large sample may ask participants about the testing
experience
Analyzing the Results
can gather both quantitative and qualitative information
use quantitative information for such things as item characteristics, internal consistency, convergent and discriminate validity, and in some instances predictive validity
Revising the Test Choosing the final items requires
weighing each item’s content validity, item difficulty and discrimination, inter-item correlation, and bias
when new items need to be added or items need to be revised, the items must again be pilot tested to ensure that the changes produced the desired results
Validation and Cross-Validation Validation is the process of obtaining
evidence that the test effectively measures what it is supposed to measure (i.e., reliability and validity)
first part of establishing content validity is carried out as the test is developed--that it measures the constructs (construct validity) and predicts an outside criterion is determined in subsequent data collection
Validation and Cross-Validation when the final revision of a test yields
scores with sufficient evidence of reliability and validity, test developers then conduct cross-validation--a final round of test administration to another sample
because of chance factors the reliability and validity coefficients will likely be smaller in the new sample--referred to as shrinkage