Psychology 340 Exam 1

Card Set Information

Psychology 340 Exam 1
2011-02-08 03:09:18
UIC Psychology

Psychological Testing
Show Answers:

  1. The basis of psychological testing is...
  2. What are test used for when it comes to psychology?
    A test is a measurement device or technique used to quantify behavior or aid in the understanding or prediction of behavior.
  3. Item
    Is a specific stimulus to which a person responds overtly
  4. Scales and Raw scores
    Scales relate raw scores on test items to some theoretical or empirical distribution.
  5. What are test good for?
    • Measure current behavior
    • Predict future behavior
    • Infer hidden behavior
  6. Test can measure...
    • States-temporal; change
    • Traits-fixed
  7. Test can be given to...
    • The individual
    • A group
  8. Types of Test...
    • Ability test-measure previous learning
    • Aptitude test-measure potential for acquiring a particular skill
    • Intelligence test-measures intelligence
  9. Intelligence refers to...
    • A person's general ability to...
    • solve problems
    • adapt to changing circumstances
    • think abstractly
    • profit from experience
  10. First test...
    Chinese civil service test
  11. In 1883...
    The American government established the American civil service commission
  12. James Cattell
    Developed mental test
  13. Seguin Form Board
    Developed to educate and evaluate the mentally handicapped.
  14. Standardization sample
    A group given the test under standard conditions.
  15. Representative sample
    A sample that represents the group we are using comparisons.
  16. Mental Age
    How you perfomed compared to others who took the test.
  17. Personality test
    • Stimulus
    • Response
    • Projective
    • Ambiguous
    • Face-Valid
  18. The Rorschach
    • Inkblot
    • Could not find meaningful standardized responses
    • Still widely used
    • Full of
  19. MMPI-Minnesota Multiphasic Personality Inverntory
    uses empirical methods (factor analysis) to determine of a test response
  20. What do statistics provide?
    • Concise descriptions of lots of quantitative information.
    • demographic breakdown
    • prevalance of behavior
  21. To Infer things...
    • Deduce things you cant observe directly.
    • Measure something in a small group of ppl.- the sample
    • Infer the results apply to a larger group of ppl. - the population
  22. Measurements
    using rules to assign numbers to objects
  23. Scales have 3 properties...

    Equal intervals-difference between any 2 points on the scale is the same

    Absolute zero- it is possible to have none of the quality measured
  24. Types of Scales
    Nominal-not really scales, assigning random designator numbers to ppl or things

    Ordinal-have moreness but not equal intervals or absolute zero. E.g. putting ppl in order shortest to tallest

    Interval- have magniude and equal intervals but not necessarily absolute zero. E.g. temperature

    Ratio- have magnitude, equal intervals and absolute zero
  25. Frequency Distribution
    Displays how many times (frequency) each score (distribution) was obtained on a scale.

    • x-axis=each score, from lowest to highest
    • y-axis= # of times each score was obtained
  26. Normal Distribution
    Increased sample size; bell-shaped curve
  27. Skew
    • pos.=tails to the right
    • neg.=tails to the left

    IQ scores have a pos. skew
  28. Class interval
    The distance between two consecutive measurements in your distribution.
  29. Percentiles
    Indicate the particular score below which a defined percentage of scores falls.
  30. Quartile system
    Divide the percentage scale into four groups
  31. Decile system
    Divide the scale into tenths
  32. Stanines
    Divide the scores into standard 9ths

    this creates 3 groups= the lower, middle and high group
  33. Interquartile range
    The middle 50% of scores (25%-75% percentiles)
  34. Mean
    The average score in a distribution

    mean= (sum of all scores) / (# of scores)
  35. Median
    The point at which 1/2 the scores are above and 1/2 are below
  36. Mode
    The "bump"

    most common score
  37. Variance*
    The variation of the scores around the mean
  38. Standard Deviation*
    The average deviation around the mean

    calculation: SD=Square root of the variance
  39. Z-scores*
    Indicate how far from the mean a score is

    universal expression of SD

    • scores above the mean are + z-scores
    • scores below the mean are - z-scores

    between -3.0 and +3.0
  40. McCall's T; T-Scores
    The mean did not equal 0, as it is with z-scores it equaled 50

    standard deviation did not equal 1, as it is with z-scores it equaled 10
  41. Transformation
    Mathematical translation; transformations standardize the distribution.
  42. Norms
    • Average performance by standardization sample
    • The standardization sample sets the norms
  43. Norm-Referenced Tests
    • Compare individuals to a normative group
    • E.g. class exam scores
  44. Criterion-Referenced Tests
    Compare an individual to a criterion on a specific skill, tasks, or knowledge
  45. Variable
    • A measure that can have multiple values
    • E.g. weight, test score, etc.
  46. Co-Vary
    As on changes, another changes
  47. You can measure changes using...
    • Correlation
    • Regression
    • Multiple regression
  48. Scatter Plots
    A picture of the relationship between 2 variables

    One variable increases on the horizontal, or x-axis

    One variable increases on the vertical, or y-axis
  49. The Regression Line
    Help us make predictions between scores of two variables

    Like a slope line on a graph

    • steep= x may predict y
    • flat= y may predict x

    a= y-bx
  50. The Residual
    The difference between the actual score and the predicted score

    the best fitting line minimizes the residual
  51. Correlation
    correlation is like regression, except scores from each variable are standardized
  52. Correlation coefficient
    Describes the magnitude and direction of relationship between 2 variables

    • Number...
    • -1.0 - +1.0
  53. Types of correlations
    • Pos.- variables 1 and 2 go up or doen together
    • Neg. - variables 1 and 2 move in opposite directions
    • No correlation
  54. Pearson's r
    The statistics used to measure correlation
  55. Null Hypothesis
    Assume that there is no relationship between 2 variables
  56. Pearson's r is used for...
    2 countinuous variables
  57. Dichotomous variables
    yes/no; true/false; pass/fail; etc...

    All dichotomous variables are categorical

    No Pearson's r for dichotomous variables
  58. Biserial correlation
    Between one continuous and one dichotomous variable
  59. Standard error of estimate
    • The standard deviation of the residuals
    • Predicts fit of the regression line
    • Smaller is better
  60. Coefficient of determination
    • The correlation coefficient squared (r2)
    • Indicates how much of the variation in Y is due to X
  61. Cross Validation
    Using the regression equation from one group of subject to predict performance in a different group of subjects
  62. Shrinkage
    The amount of decrease in predictability from cross-validating
  63. Restricted Range
    If the variability of a variable is extremely restricted, significant correlations may be difficult to find even if they are there
  64. Factor analysis
    Creates factors: groups of related variables
  65. Reliability
    Is all about error.
  66. Error
    • Difference in true ability and measurement of ability.
    • The inevitable inaccuracy of our measurements.
    • How much our test do not reflect reality.
  67. Psychological testing tries to...
    • find the magnitude of error for each test
    • try to minimize error for all tests
  68. Tests that are relatively free from error are...
  69. Yardstick
    measure tangible things
  70. Rubber yardsstick
    • measure intangible things
    • one that may over or under estimate the measurement
  71. Test score theory
    • Influences how we think about and calculate reliability
    • assumes each person has a true score

    • We do not report the true score
    • we report the observed score
  72. The distribution of random error is...
  73. Narrow distribution
    Is accurate
  74. Wide distributioin
    Is inaccurate
  75. Methods that measure reliability
    • Time-sampling
    • test-retest method
    • Item-sampling
    • parallel forms method
    • split-half method
  76. Test-Retest Method
    • Administer the test at 2 different times
    • compare each test-takers scores

    • Caveats:
    • stable traits
    • carry-over effects
  77. Internal Consistency (IC)
    when the variance is equal on different parts of the test
  78. 2 types of test to calculate IC
    Dichotomous test & Likert scales
  79. The reliability statistic
    α alpha
  80. The variance of the true scores
  81. The variance of the observed scores
  82. Domain Sampling Model
    • Uses a sample of items, not the entire domain of items
    • pick several items from your original test
    • give that small test
    • record observed scores
    • estimate true scores fro these observed scores
    • More items = more reliability (generally)
  83. Adaptive test
    Test that adapts to the test taker
  84. Reliability of a Difference score (RDS)
    • Subtract one score from another
    • same test given at 2 points in time
    • 2 sub-scores from one test
  85. RDS rule
    Make the comparison in Z-units
  86. Problem with RDS
    • The error of a difference score is inflated
    • It absorbs error from both scores in the difference score.
  87. Potential solution to RDS
    Calculate RDS if you know... α of each test and r between these test
    Even tests with high α and r may have low RDS
  89. Interrater Reliability
    The similarity of rater 1 and rater 2's measurements
  90. Agreement for Interrater reliability
    • K = Pr (a)-Pr (e)
    • 1-Pr (e)

    • -1.0 - 4.0