Class Notes (836,990)
Canada (510,026)
Psychology (7,785)
PSYC37H3 (113)
Lecture 5

Lecture 5.docx

8 Pages
116 Views
Unlock Document

Department
Psychology
Course
PSYC37H3
Professor
Anthony Ruocco
Semester
Winter

Description
Psychological Assessment - Lecture 5; Feb 5, 2013 Validity and Test Development Validity: A Definition  A test is valid to the extent that inferences made from it are appropriate, meaningful, and useful - us trying to get evidence as researchers to see if the test measures what it is really supposed to measuring  A unitary concept is determined by the extent to which a test measures what it purports to measure Validity as a Developmental Process  Begins with test construction and continues indefinitely - designing the test  Test validity hinges upon the accumulation of research findings  For example, transition from the third to the fourth edition of the Wechsler Adult Intelligence Scale (WAIS) Content Validity  Determined by the degree to which the questions, tasks, or items on a test are representative of the universe of behavior the test was designed to sample - what should we be testing? 1 Psychological Assessment - Lecture 5; Feb 5, 2013 Content Validity Coefficient  Content validity = D/(A + B + C + D)  Divide the number of times people agree by all other possibilities  For Figure 4.3: Content validity = 87 / (4 + 4 + 5+ 87) = 0.87 Face Validity  A test has face validity if it looks valid to test users, examiners, and especially the examinees - sometimes you don't want it to have face validity because you might not get at what you want if the participant knows and the participant can lie Criterion - Related Validity  Criterion-related validity is demonstrated when a test is shown to be effective in estimating an examinee’s performance on some outcome measure - we know that the test has this validity if it associates with the real world  The variable of primary interest is the outcome measure, called a criterion  Characteristics of a good criterion: (a) reliable and (b) free of contamination from test itself - criterion cannot be contaminated by the thing you want to measure 2 Psychological Assessment - Lecture 5; Feb 5, 2013 Types of Criterion - Related Validity  Concurrent validity  Test scores and criterion information are obtained simultaneously; ex: patient actually calling 911 vs. getting patient to call 911 on a fake phone  Predictive validity  Test scores are used to estimate outcomes to be measured at a later date - not measuring the other thing at the same time; ex: when someone is first complaining and test them and then survey the family members 10 years later What about the Graduate Record Examination (GRE)?  Predictive validity is actually very weak in terms of success in graduate studies in psychology  Validity coefficients range from .30 to .45 between the GRE and both first year and overall graduate GPA in a study conducted by Educational Testing Services  GRE is not predictive of success in graduate school Decision Theory  One purpose of psychological testing is measurement in the service of decision making - there is going to be error in decision, never perfect  False positive (e.g., persons predicted to succeed actually fail) ; someone's going to pass but actually fail  False negative (e.g., persons predicted to fail actually succeed); someone's going to fail when they actually succeeded - bad decision Examples of "False" Decisions  Airport Security: a “false positive” is when ordinary items (e.g., keys or coins) get mistaken for weapons  Quality Control: a “false positive” is when a good quality item gets rejected, and a “false negative” is when a poor quality item gets accepted  Antivirus software: a “false positive” is when a safe file is thought to be a virus  Medical screening: low-cost tests given to a large group can give many false positives (i.e., saying you have a disease when you actually do not), and then ask you to get more accurate tests how might a false positive diagnosis of Alzheimer's disease be made based on an older adults' scores on the Independent Living Scales? if the person gets a low score and say that they have a loss of independence when they actually do not. 3 Psychological Assessment - Lecture 5; Feb 5, 2013 Construct Validity  A construct is a theoretical, intangible quality or trait in which individuals differ - we assume people differ in intelligence, we need to have a way of testing to see if the test measures what its supposed to be measuring - people have this thing that we're trying to measure and the way to measure is it is with the test  Examples include: leadership ability, over-controlled hostility, depression, and intelligence - assume people have these things so our test is designed to measure this  Can be considered the unifyin
More Less

Related notes for PSYC37H3

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit