CRJ Introduction To Research Design In Criminal Justice: Concepts, Operationalization, and Measurement PDF

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CRJ Introduction To Research Design In Criminal Justice Class Notes: Concepts, Operationalization, and Measurement...

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Research Methods in CRJ Chapter 5 Concepts, Operationalization, and Measurement INTRODUCTION Because measurement is difficult and imprecise, researchers try to describe the measurement process explicitly We want to move from vague ideas of what we want to study to actually being able to recognize and measure it in the real world Otherwise, we will be unable to communicate the relevance of our idea and findings to an audience What is measurement?  like rating or assigning labels to units of analysis CONCEPTIONS AND CONCEPTS Clarifying abstract mental images is an essential first step in measurement Conception – Mental image we have about something Concepts – Words, phrases, or symbols in language that are used to represent these mental images in communication Concepts are constructs derived by mutual agreement from mental images e.g., gender, punishment, chivalry, delinquency, poverty, intelligence, racism, sexism, assault, deviance, income THREE CLASSES THAT SCIENTIST MEASURE Direct observables Those things or qualities we can observe directly (color, shape) Indirect observables Require relatively more subtle, complex, or indirect observations for things that cannot be observed directly (reports, court transcripts, criminal history records) Constructs Theoretical creations; cannot be observed directly or indirectly; similar to Concepts CONCEPTUALIZATION

The process through which we specify what we mean when we use particular terms in research We cannot meaningfully answer a question without a working agreement about the meaning of the outcome Conceptualization produces a specific, agreed-upon meaning for a concept for the purposes of research Results in a set of indicators of what we have in mind Question: females less deviant than males? – what does it mean to be deviant? INDICATORS AND DIMENSIONS Indicator – an observation that we choose to consider as a reflection of a variable we wish to study What is deviant? – shoplifting as indicator – underage drinking- vandalizing property – give indicator score of 1 then add up – ( links back to females or males more deviant question) Dimension – a specifiable aspect of a concept “Crime Seriousness” – Can be subdivided into dimensions e.g., Dimension – Victim harm Indicators – Physical injury, economic loss, psychological consequences Specification leads to deeper understanding CONCEPTUALIZATION The Interchangeability of Indicators If several different indicators all represent the same concept, all of them will behave the same way the concept would behave if it were real and could be observed CONFUSION OVER DEFINITIONS AND REALITY Concepts are abstract and only mental creations The terms we use to describe them do not have real and concrete meanings What is poverty? delinquency? strain? Reification – Process of regarding as real things that are not CREATING CONCEPTUAL ORDER Conceptual definition (what is SES?)

Working definition specifically assigned to a term, provides focus to our observations Gives us a specific working definition so that readers will understand the concept Operational definition (how will we measure SES?) Spells out precisely how the concept will be measured

DEFINITIONS IN DESCRIPTIVE AND EXPLANATORY STUDIES Definitions are more problematic for descriptive research than for explanatory research The degree of precision needed varies with the type and purpose of a study OPERATIONALIZATION CHOICES Operationalization – The process of developing operational definitions Moves us closer to measurement Requires us to determine what might work as a data-collection method MEASUREMENT AS SCORING Measurement – Assigning numbers or labels to units of analysis in order to represent the conceptual properties Make observations, and assign scores to them Difficult in CJ research because basic concepts are not perfectly definable EXHAUSTIVE AND EXCLUSIVE MEASUREMENT Every variable should have two important qualities: Exhaustive – You should be able to classify every observation in terms of one of the attributes composing the variable

Mutually exclusive – You must be able to classify every observation in terms of one and only one attribute OPERATIONALIZATION CHOICES Levels of Measurement NOMINAL ORDINAL INTERVAL RATIO LEVELS OF MEASUREMENT Nominal Variables whose attributes are merely different; they have only the characteristics of exhaustiveness and mutually exclusiveness; offer names or labels for characteristics Examples: sex, religious affiliation, college major, hair color, birthplace, nationality Ordinal Variables with attributes we can logically rank in order Examples: socioeconomic status, level of conflict, prejudice, conservativeness, alienation Interval Variables whose attributes are rank-ordered and have meaningful distances between adjacent attributes Examples: temperature (Fahrenheit), IQ score

IMPLICATIONS OF LEVELS OF MEASUREMENT Determines the arithmetic operations that can be applied to a variable

CRITERIA FOR MEASUREMENT QUALITY

Reliability – the quality of measurement method that suggests the same data would have been collected each time in repeated observations of the same phenomenon Problem: Even if the same result is retrieved, it may be incorrect every time Reliability is not the same as accuracy

Observer’s subjectivity might come into play METHODS OF DEALING WITH RELIABIILITY ISSUES Test-Retest Method Make the same measurement more than once –expect same response Interrater Reliability Compare measurements from different raters; verify initial measurements Split-Half Method Make more than one measure of any concept; see if each measures the concept differently CRITERIA FOR MEASUREMENT QUALITY Validity – a term describing a measure that accurately reflects the concept it is intended to measure Are you really measuring what you say you are measuring? Demonstrating validity is more difficult than demonstrating reliability METHODS OF DEALING WITH VALIDITY ISSUES Face Validity – On its face, does it seem valid? Does it jibe with our common agreements and mental images? Criterion-Related Validity– the degree to which a measure relates to some external criterion Construct Validity – Whether your variable relates to another in the logically expected direction Content Validity – Does the measure cover the range of meanings included in the concept? Multiple Measures – Alternative measures CRITERIA FOR MEASUREMENT QUALITY

An Analogy to Validity and Reliability. A good measurement technique should be both valid (measuring what it is intended to measure) and reliable (yielding a given measurement dependably). COMPOSITE MEASURES Allow us to combine individual measures to produce more valid and reliable indicators Reasons for using Composite Measures: The researcher is often unable to develop single indicators of complex concepts We may wish to use a rather refined ordinal measure of a variable, arranging cases in several ordinal categories from very low to very high on a variable such as degree of parental supervision Indexes and scales are efficient devices for data analysis TYPOLOGIES Taxonomy Produced by the intersection of two or more variables to create a set of categories or types e.g., Typology of Delinquent/Criminal Acts (Time 1 and 2) None, Minor (theft of items worth less than $5, vandalism, fare evasion), Moderate (theft over $5, gang fighting, carrying weapons), Serious (car theft, breaking and entering, forced sex, selling drugs) Nondelinquent, Starter, Desistor, Stable, De-Escalator, Escalator INDEX OF DISORDER What is disorder? (Skogan, 1990) Distinguish between physical presence & social perception Physical disorder: Abandoned buildings, garbage and litter, graffiti, junk in vacant lots Social disorder: Groups of loiterers, drug use and sales, vandalism, gang activity, public drinking, street harassment Index created by averaging scores for each measure BENEFIT OF INDEXES...