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PSYC 204- ASSIGN2
In class assignment 2
| Term | Definition |
|---|---|
| Nominal Scale | -Data can be categorized --Numbers represent categories --No overlapping values |
| Ordinal Scale | -Data can be categorized, ranked (relative to other categories) --Cannot be used to derive statistics like arithmetic mean --Likert Scales |
| Interval Scale | -Data can be categorized, ranked, evenly spaced/equal values between intervals (no ambiguity) --No true zero |
| Ratio Scale | -Data can be categorized, ranked, evenly spaced/equal values between intervals, and has a natural zero. --Allows make of proportional statements about measurement data ---Only proportional statements about non-zero numerical values ---Temperature |
| Two rules of nominal scale | -Mutual exclusion -- A "case" (what you're measuring) can only fit into one category -Exhaustivity --Include a residual category (other/unsure) |
| Nominal scale: Predefined Response Categories vs. Specify Responses | -Other -Other please specify: ______ --Provides info that researchers might not have anticipated when designing a measure |
| Residual categories | -Attempt to capture missing data -- Other/unsure/specify___ |
| Direct vs. Indirect Indicators | Direct: -Indicator is an indicator of another thing Indirect: -Sherlock logic |
| Multiple Indicator Measures (MIM) | - For abstract or complex variable measurement (ex. intelligence) -Measure dimensions of a variable (ex. subtypes) |
| Categorical data | Nominal or ordinal scale |
| Continuous data | Interval or ratio scale |
| Reliability | Consistency in results |
| Validity | If the measure actually measures what it's designed to -All or nothing (ex. yes or no) |
| Reliability Test: Test-Retest Reliability | Test something using a measurement instrument and then test the same thing again to see if the result is same |
| Reliability Test: Equivalent Forms | -When equivalent tests exist, researchers build a question bank and use these to create multiple versions of a test --Rewording questions on the test/measure |
| Stats: Response Similarity | -Item by item comparisons of responses --Mode (with categorical measures) OR -Aggregate score comparisons --Mean comparison or correlational analysis (interval or ratio level data) |
| Stats: Response Similarity: BEWARE | -Altering precisely worded questions may alter the meaning/responses --Underestimating a statement change's affect on the degree of reliability |
| Reliability Test: Internal Consistency Reliability | -Used in MIM when indicators measure the same thing --Using Split-Half method |
| Split-Half Method | -Internal consistency reliability -Split indicator data into two sub-groups, then compare results using correlational analysis |
| Stats: Split-Half Method: BEWARE | -Some test items will measure different dimensions of a variable --Low correlation may make a measure seem less reliable than it actually is |
| Reliability Test: Inter Rater Reliability | -Based on level of agreement between two or more independent observers (who are studying the same thing) --Quality consistency |
| Pseudo-scientific theories | -Based on reliable but invalid measurements |
| Accuracy | -Degree of truth |
| Evidence for Validity (based on content): Face Validity | -Extent to which a measure/indicator seems like it measures what it claims to measure |
| Face Validity: BEWARE | -Easier for test taker to "game" tests (produce an outcome they want) --Reduces reliability |
| Fix: Face Validity | -Use indirect measures with low face validity (harder for test taker to interpret) --Less obvious answer ---Lower chance of participants being able to "game" the test |
| Evidence for Validity (based on content): Psychometrics | -Specialized in measurement and testing --Determine if someone is actively trying to "game" the test/isn't paying attention ^By comparing high face validity and low face validity/indirect question responses: ---similar=unlikely ---dissimilar=likely |
| To "game" a test | -Knowingly or unknowingly manipulating results of a test to achieve a desired outcome |
| Evidence for Validity (based on content): Criterion Validity | -How well a measure compares to another, well established measure |
| Criterion Validity: BEWARE | -Be sure the comparative measures are valid too --Investigate sources of "valid" information! |
| Evidence for Validity (based on content): Predictive Validity | -Predictive accuracy based on present data (or "scores") --Predict an outcome based on correlational data |
| Statistic | -An ESTIMATE of the parameters of a population --Stats are always/only an estimate |
| Parameters | -Actual characteristics of a population |
| Error | -Difference between sample statistic and population parameter --"Luck of the draw" phenomenon ---Sample population "luck of the draw" type condition ----May not represent general population |
| 2 Ways to Reduce Errors (caused by sampling) | 1. Increase sample size 2. Improve representativeness -Random sampling |
| Random Sampling | -Each member of a population has equal chance to be chosen for participation --EPSEM rule (equal probability of selection method) |
| Sampling Procedures(3): Identify Target Population | 1. Identify target population 2. Element list -Eligibility criteria --Pool from which the sample is drawn 3. Decide on sample type |
| Purpose of Samples | -Samples are used to make generalizations about populations |
| Random Sampling: BEWARE | - Obtaining diverse participants for research --Response rates differ among different groups of people |
| Types of Strategic Sampling | -Cluster sampling -Stratified sampling |
| Cluster Sampling | -Split an element list into several sub-categories and use census data to find population percentages, then randomly sample participants in their matching categories from the element list |
| Strengths and Weaknesses: Cluster Sampling | Strength: -Improves representativeness -Preserves EPSEM principle Weakness: -Sampling error is greater because each sub-category contains smaller participant samples |
| Stratified Sampling |