Learning Objectives In this chapter you will learn about the elements of the research process some basic research designs program evaluation the justification for following the steps in the research process

Elements of the Research Process Basic elements of research include  theory  a probabilistic statement about reality  hypotheses  a testable statement based on theory  variables  constructs whose values vary

Validity & Reliability Two key research concepts  validity  the accuracy of a measure  reliability  the consistency of a measure across some aspect, such as time

Validity Four categories of validity  internal  external  statistical conclusion  construct

The Research Process Steps include I. Problem Identification II. Research Design III. Data Analysis IV. Interpretation and Presentation of Results

Problem Identification Problem identification includes  Concepts  Hypotheses  Variables

Research Design Research design includes  Type of Design  Sampling Method  Data Collection

Sampling Two broad categories of samples  random (probability)  non-probability (available samples) Results of research  inferred from sample to population if  sample is random (representative)

Data Collection Data collection involves  identification and selection of data sources  sources include  original data (surveys, experiments, etc.)  archival data (official records, official data, etc.)

Data Analysis Data analysis involves  Selection of Statistical Method  Calculation of Statistic  Interpretation of Statistic

Data Analysis Data analysis involves  entering the data into a database after it is collected  selecting the proper method of analysis, which depends on  the type of data collected  the research question

Interpretation & Presentation Interpretation and presentation of results involves  a written summary of the results  including policy implications, if any  presentation in a public forum  publication (if the results warrant it)

Elements of the Scientific Method Hypothesis  formal statement about the expected relationship between variables Independent variable (X)  produces an effect on the dependent variable (Y) Dependent variable (Y)  may change due to the independent variable

Elements Directional hypothesis  the independent variable is expected to influence the dependent variable in a specified direction – negatively or positively Variable  designed to measure observations or concepts. It usually has more than one possible value

The Classical Experiment Classical or True Experimental Design  involves the assignment of subjects to the experimental (receives the treatment) and control groups Random assignment  every member of target population has an equal chance of being selected for the experimental or control group

Classical Experiment RO 1 XO 2 Experimental Group RO 3 O 4 Control Group Where: R = Random assignment O 1 and O 3 are Pre-tests O 2 and O 4 are Post-tests X = treatment (I.V.) The classical experimental design can be diagramed as illustrated

Quasi-experimental Design Quasi-experiments differ from classic experiments  lack an equivalent control group  may even lack any type of control group – ex. one-shot case study

Quasi-experimental Design O 1 XO 2 Experimental Group O 3 O 4 Control Group Where: O 1 and O 3 are Pre-tests O 2 and O 4 are Post-tests X is the treatment (I.V.)

Evaluation Research Evaluation research  addresses the ability of a program or policy to accomplish its goals  is action-oriented, policy research  is specifically designed to guide decision making

Benefits of Research Problem-solving focus  provides direction for crime prevention programs  promotes efficient utilization of resources  identifies what does and does not work  assists in decision to revise or eliminate policies

Application of Research Process An example of applied research is COMPSTAT  using data analysis to identify key problems  dependent on the flow of information  dependent on accurate and timely intelligence on crime and community conditions

Summary This chapter presented  basic elements of research  a description of the “formula” that social scientists and practitioners follow  a justification for following the formula  obtaining valid and reliable data to use for decision making