CCJ 4700 Exam 2 Study Guide Conceptualization definition process by which we specify what we mean when we use particular terms mental process whereby fuzzy and imprecise notions are made more specific and precise The product is a specific agreed upon meaning for a concept Operationalization definition process of developing an operational definition Operational definition definition in terms of specific operations measurement instruments or procedures Typologies definition classifying observations in terms of their attributes Sometimes called taxonomy Created with nominal variables Produced by intersection of 2 or more variables to create a set of categories or types Example Classify people according to range of their experience in criminal court 3 Sources for Measuring Crime 1 Official stats 2 Victimization Survey 3 Self report Survey Reliability definition consistency of measurement Measures are reliable if researchers obtain same results when measuring something more than once o Equivalence reliability Inter rater reliability used to assess different interviewers coders or other research workers to give consistent results Supervisors guard against interviewer reliability by calling participants on the phone and verify selected information Intra rater reliability degree of stability observed when a measurement is repeated under identical conditions by the same rater Intra rater reliability makes it possible to determine the degree to which the results obtained by a measurement procedure can be replicated o Representative reliability represents the whole population that has similar answers o Internal consistency reliability used to assess the consistency of results across items construct idea within the same test o Know the different ways you can improve reliability 1 Conceptualize clearly 2 Increase the level of measurement 3 Use multiple indicators 4 Use pretests and pilot studies 5 Use established measures 6 Training of research workers interviewers Validity definition measures the extent to which the measure actually reflects the real meaning of the concept it is supposed to measure o Internal validity vs external validity 1 Internal validity whether observed associations b t 2 variables are causal associations or are due to the effects of some other variable 2 External validity whether a relationship observed in a specific population at a specific time and in a specific place would also be observed in other populations at other times and in other places a Concerned with generalizability o Generalizability quality of research finding that justifies the inference that it represents something more than the specific observations on which it was based o Construct validity based on the logical relationships among variables o Criterion validity compare the results f the measure to some trustworthy alternative measure Predictive validity where an indicator predicts future events that are logically related to a construct o Face validity making sure the measurement makes sense o Threats to internal validity 1 Compensation treats differently than other group 2 Compensatory rivalry control group competes compensate Levels of measurement o Nominal indicated only that there is a difference b t categories Example gender city of residence college major ssn and marital status o Ordinal indicate that there is a difference plus the categories can be ordered or ranked Example opinion of police occupational status crime seriousness fear of crime o Interval indicate categorical differences that can be rank ordered but they also specify the distance b t categories Example standardized intelligence test o Ratio include everything in the previous 3 levels plus there is a true zero makes proportions ratios possible Example age dollar value of property loss from burglary number of prior arrests BAC and length of incarceration o Hierarchy among levels of measurement 3 Ordinal 1 Ratio 2 Interval 4 Nominal Types of Measure Type of Info Classification Rank Order Equal Intervals Non arbitrary Zero Nominal Ordinal Interval Ratio X X X X X X X X X X The classic experiment definition research design well suited to inferring cause o Randomization What is it Technique for randomly assigning experimental subjects to experimental groups and control groups Why is it important Central feature of classical experiment Produces experimental and control groups that are statistically equivalent o Features of the classical true experiment The classical experiment involves 3 major pairs of components independent and dependent variables pretesting and post testing and experimental and control groups w random subjects randomly assigned o Different variations of the classic experiment 1 Double Blind Experiment 2 Post test Only Design 3 Factorial Design 4 Solomon Four Group Design Which of these is the best for reducing threats to validity Solomon Four Group Design Classic and the BEST Quasi experimental design o No randomization o Time series designs Oversimplifies 1 Measurements taken over time 2 Interrupted time series 3 Interrupted time series w matching 4 Interrupting time series w removed treatment 5 Interrupted time series w switching replications Why would you use one over another Depending on the case studies the attention centers on the of subjects or cases in the study o Non equivalent group design Matching Experimental and control groups do not utilize randomization Selection bias is a threat to internal validity Precision vs aggregate matching Aggregate matching is matching by group Precision matching is specific matching Characteristics of a probability sample o Representativeness factors may affect research question Sample needs to look like population o Randomness Every person has a known chance of selection Probability of selection is known o EPSEM Equal Probability of Selection Method o No selection bias when using probability sampling technique o Sampling unit element unit that provides the basis of analysis o Sampling error random error due to the fact that the entire population was not sampled o Sample bias systematic differences between the sample and the population due to sampling Probability Sampling procedures o Sampling frame list of elements in our population o Sampling distribution Range or array of sample stats we would obtain if we drew a very large number of samples from a single population o Confidence level vs confidence interval 1 Confidence interval CI range of values within which a
View Full Document
Unlocking...