#  A Test Must Be: ◦ Reliable ◦ Valid ◦ _____________________ = consistent ◦ _____ = measuring what it is suppose to measure.

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 A Test Must Be: ◦ Reliable ◦ Valid ◦ _____________________ = consistent ◦ _____ = measuring what it is suppose to measure

Reliability Validity Construct Criterion Content Interrater Face

Reliability and Validity Reliable but not valid

Reliability and Validity Neither reliable nor valid

Reliability and Validity Reliable and valid

reliability = refers to test's consistency A reliable test minimizes error and provides repeatable consistent results

 1) low precision ◦ characteristics of the instrument used  2) state of the participants ◦ depressed, moody, irritable  3) state of the experimenter ◦ depressed, moody, irritable…  4) state of environment ◦ noise, heat, etc.

1234512345 1234512345 3Scan a multitude of information and decide what is important. 1234512345 1234512345 1234512345 1234512345 1234512345 1Manage time effectively 2Manage resources effectively. 3Scan a multitude of information and decide what is important. 4Decide how to manage multiple tasks. 5Organize the work when directions are not specific. 1Manage time effectively Rating Sheet Observedscore = Trueability + Randomerror Te+

Correlations used Normally ranges from -1.0 to +1.0. Reliability coefficient is: __________________

Test-retest Alternate Forms Internal Consistency Inter-rater

 Coefficient of stability is the correlation of the two sets of test scores.

 Two versions of the same test with similar content  Forms must be equal

 Split half  KR-20  Cronbach’s alpha

 Measures scorer reliability  Do the judges agree?

 Scores by two independent judges and the scores are correlated  _________________________

 research  clinical settings

Reliability Validity Test-Retest IC Alternative Construct Criterion Content Convergent Discriminant Factorial Interrater Face

Neither Reliable or Valid Highly Reliable but Not Valid Highly Reliable and Valid

 Definition  Face Validity  Content Validity  Criterion-Related Validity  Construct Validity

 The extent to which a test measures a trait that it claims to measure  Involves “Validation”

 superficial examination of domain  Does the test "look valid?“

 Does the test assess the domain of the construct that is supposed to measure?

 involves examination of the literature  domain must be systematically analyzed  consult with experts in the field

 Biases ◦ Consider biases of the panelists  Level of expertise of the panelists ◦ Are they really experts?

 relationship between test and criterion Criterion (Y) (behavior) Predictor (X) (test) - SAT GPA SAT = Scholastic Achievement Test GPA = Grade Point Average

 Concurrent  Predictive

 test and criterion are measured at approximately the same time

 The extent to which a test measures a theoretical construct  Construct ◦ A scientific concept to describe a psychological trait - e.g., anxiety, depression, or intelligence

 Validation occurs through a pattern of consistent findings with different tests across various settings Test Your Test Gold Standard

 Convergent validation  Discriminant validation

 A test should correlate highly with another test that is theoretically related Your Test – IQ Measure Gold Standard WAIS WAIS = Wechsler Adult Intelligence Scale r = positive and strong

 A test ought not to correlate with a theoretically unrelated test Your Test – IQ Measure Extraversion r = close to zero

 Campbell & Fiske (1959)  Correlation of: ◦ 2 or more traits by 2 or more methods  Methods: ◦ e.g., self-report v. peer observations  Traits: ◦ e.g., Extraversion and Warmth

 reliability  Same trait, same method  High r, ___________________  Low r, ___________________

 Same trait, different method  Validity coefficients expected to be high  High r, __________________________  Low r, _______________________

 Different trait, same method  Coefficients expected to be low to moderate  high r, ________________________  low r, ___________________________

 Different trait, different method  Coefficients expected to be the lowest  high r, ________________________  low r, __________________________

EsEpAsAp EsMMMHHMHH EpMMHHHM AsMMMH ApMM (reliability)

 Basic Idea: ◦ Personality is projected onto the stimulus  Varieties ◦ TAT ◦ Inkblot ◦ Incomplete Sentence Blank

 Thematic Apperception Test (1935)  Henry Murray  Christina Morgan

 Hermann Rorschach (1921)  10 inkblots  Holtzman Inkblot technique (HIT)  45 inkblots

 My greatest fear…  My mother…  Men…

 Strength  1)  2)  Weakness  1)  2)

 Hathaway and McKinley  Assesses mental health  MMPI, MMPI-2 (1989)

 8 MMPI clinical scales developed from 8 groups of psychiatric inpatients.  Social Introversion and Masculinity-Femininity were added later.  16 years old, grade 6 education

 Validity scales: ◦ L scale or lie scale ◦ F scale or Infrequency scale ◦ K scale or correction scale ◦ ? Cannot Say

 1 Hypochondriasis (Hs)

 2 Depression (D)

 3 Hysteria (Hy)

 4 Psychopathic Deviate (Pd)

 5 Masculinity-Femininity (Mf)

 Scale 6: Paranoia (Pa)

 Scale 7: Psychasthenia (Pt)

 Scale 8: Schizophrenia (Sc)

 Scale 9: Hypomania (Ma)  tends to assess:

 advantages  very comprehensive  lot of literature  professional communication  computerized

 disadvantages  somewhat out of date with existing diagnostic categories  the instrument takes about 30 minutes to one hour to complete

 1) ___________________  2) ______________________  3) __________________

Life and Death a Serial Killer (Broomfield & Churchill, 2002) Case Study…

 Jan 9, 1991 – arrested in Florida  paranoid, borderline personality disorder  admits that she lied on the stand about self defense  did it to “come clean”  killed because of robbery and to eliminate a witness  plan murders, selected the men  “there was no self-defense”

 “the world is full of evil”  made 200-300 a day as prostitute  met Tyra in bar, lesbian relationship  Tyra made a state’s witness  Tyra not charged in the murders  participated with police  sorry about her actions

 “doing lying biz to beat the system”  her report of Richard Mallory was convincing  Mallory spent 5 years in jail for sex crimes  “you have to kill Aileen Wournos because she will kill again”  talked about conspiracies in early 1990s  tended to sabotage own defense

 oral sex for cigarettes at age of 9  incestuous relationship with brother Keith  Aileen’s grandfather beat her with black belt  rumored that he was her biological father  Biological mother abandoned her at 6 months  “father” sent to jail for sodomizing a boy  later he committed suicide

 Had baby boy at age 13  two years living in the woods  survived by hooking  treated poorly by neighbourhood kids  father of Aileen’s child was the local pedophile

 Left Michigan at age 16  Doing drugs at time (LSD)  know for violent temper  knocked a man out with beer bottle and another with billiard ball

 Married Lewis Fell age 76  restraining charges, beat Lewis with walking stick  starting dating women in late 20s  Tyra described Aileen as –fantasist, jealous and possessive who could be violent and frightening  had fantasies of being raped

 believed police had known about the first murder but allowed her to continue  mind is being controlled by radio waves, poisoned food, threatened of rape while in prison

 I am so burning f..in mad about how I am being…  I’ve got to wait for my execution  I want to get in the f..ing chamber tomorrow and leave  And then they play, since I waived off I have nothing but  Psychological and physical f… problems, playin with it  because I am on hold with my execution.  I’m so f..in mad I can’t see straight  And they’re just daring me to kill again  They got me pissed…United States Supreme court you f…in  I’m telling you man, you motherf….  Keep f..ing with my goddamn execution and there’s going to be blood shed.  I’m sick of this, get that f..ing warrant signed.

 using “sonic pressure” on my head since 1997 ◦ (this was stated on Oct 8th, 2002).  Believes had eye in cell, believes that the tv or mirrors were rigged. Crushing my head, using sonic pressure.  Believes that police had surveillance, before she killed. It was the cops that made her do it.

 Advantage Establish causality X causes change in Y  Disadvantage May be artificial

 How would you establish this?  You need at least 2 groups ◦ Control ◦ Experimental

 IQ tested before intervention  This group receives a placebo  IQ tested after receiving placebo

IQ test prior to administering drug This group then gets the drug IQ tested again

AAre there differences before testing? if yes, sample may not be random AAre there differences after testing?

 summarized by letter r  ranges between -1 and + 1 ◦ Under ideal conditions  closer to -1 or +1, the stronger the r http://noppa5.pc.helsinki.fi/koe/corr/cor7.html

 X variable might cause the Y variable.  Y variable might cause the X variable.  Another variable influences both X and Y.  Strong correlation by chance.

 Little Albert (Watson)  Obedience (Milgram)  Stanford Prison Study (Zimbardo)

 ethics are standards regarding the treatment of others  these standards apply to both research and clinical practice  many disciplines have ethical codes  CPA (Canadian Psychological Association)  APA (American Psychological Association)

 Principle 1:  Principle 2:  Principle 3:  Principle 4:

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