# CAS 301 Study Guide

 The flashcards below were created by user reads2much on FreezingBlue Flashcards. What is a variable? What is a level or value of a variable? Variable - any event, situation, behavior, or individual characteristic that varies - that is, has at least two variables What is a level of a variable? or value of a variable? Specific instances of the variable May be quantitative/numerical Values, a number with a variable May be instances of a category Situational Variable Describe characteristics of a situation or environment May pre-exist or be manipulated by researcher - previous experiment to study things that are all ready there Predictor Variable (when pre-exists) or independent variable (when manipulated by the researcher) Response Varaible Participant's reaction to the situation Behavior/Outcome Dependent variable (when there is an independent variable) or criterion variable (where there is a predictor variable) Participant/Subject Variables Individual differences about the participant Pre-existing Predictor Variables What is a conceptual definition of a variable? The dictionary definition Explanation or description of a variable What is an operational definition? How you will measure the variable Definition in your own words What is a linear relationship between variables? How is a linear relationship measured? Linear Relationships - relationship measured with correlation coefficient and direction and strength Correlation Coefficient - Relationship between two variables What is the difference between the direction and strength of a correlation coefficient? Positive Linear Relationship One variable increases, the other variable also increases A one slope = a perfect slope Example: hot weather/crime - the higher the temp goes the higher the crime rate goesRange: 0 to 1.00 Correlation Coefficient --1.00 to 1.00 Negative Linear Relationships One Variable increases and the other variable decreasesExample: constant discipline increase, the negative behavioral problems decrease No Relationship Linear Relationships = zero There is no systematic relation between the variables Curvilinear Relationships Cannot measure with a simple correlation coefficient Increases in one variable are sometimes associated with an increase in the other variable and sometimes associated with a decrease in the other variable Increase/Increase Decrease/DecreaseIncrease/Decrease Nominal Scales No numerical values Categories Basic Scales Named Categories Anything you cannot put in order Example - gender, ethnicity, any yes/no questions Ordinal Scales Ordinal Scales - A scale of measurement in which the measurement categories form a rank order along a continuumRanked from first to last Difference between the categories is not necessarily the same Interval Scales Interval Scales - A scale of measurement in which the intervals between numbers on the scale are all equal in sizeDifference between numbers on scale is meaningful Interval are EQUAL IN SIZE No true zero Example - Temperature What is a Likert Scale? Ordinal Ordered rating categories List the major types of measures Questionnaires/Surveys Interviews Observations Direct Test What is error in a measure? Source of error - Operational definition isn't consistent: reliability Operational definition doesn't match: Validity What is reliability? Consistency or stability of a measure of behavior The degree to which a measure is consistent Test-Retest Relaibility - A reliability coefficient determined by the correlation between scores on a measure given at one time with scores on the same measure given at a later time. Internal Consistency Reliability - Reliability assessed with data collected at one point in time with multiple measures of a psychological construct. - A measure is reliable when the multiple measures provide similar results. Split-half Reliability - A reliability coefficient determined by the correlation between scores on half of the items on a measure with scores on the other half of the measure. Cronbach's Alpha - A indicator of internal consistency reliability assessed by examining the average correlation of each item (question) in a measure with every other question What is validity? - The Truth and accurate representation of information about your study and measures. Face Validity The degree to which a measurement device appears to accurately measure a variable look at the measure to see if it has "face" value Predicitve Validity Related to other things that it should be related to in the future Measure something today and compare it to something in the future Example - aggression in 10 year olds and the crime rate in the futureThe construct validity of a measure is assessed by examining the ability of the measure to predict a future behavior Concurrent Validity Related to other things that it should be related to at the same time Done at the same time Example - SAT scores senior year should be related to current GPAThe construct validity of a measure is assessed by examining whether groups of people differer on the measure in expected ways Convergent Validity Similar to other measures of the same thing Multiple measures of the same thing Example - teacher survey of children and observations of the children - they should be the sameThe Construct validity of a measure is assessed by examining the extent to which scores on the measure are related to scores on other measures of the same construct or similar constructs Discriminant Validity Different from measures of other things Low relationships between the 2 measures Personality scores should not be related to ones reading ability, therefore, no relationshipThe Construct validity of a measure is assessed by examining the extent to which scores on the measure are not related to scores on conceptually unrelated measures. What is external Validity? The degree to which the results of an experiment may be generalized. Authorreads2much ID104375 Card SetCAS 301 Study Guide DescriptionChapters 4 and 5 Updated2011-09-26T15:36:35Z Show Answers