Learning ObjectivesLearning 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 Elements of the Research ProcessProcess

Basic elements of research include theory

a probabilistic statement about reality hypotheses

a testable statement based on theory variables

constructs whose values vary

Validity & ReliabilityValidity & Reliability

Two key research concepts validity

the accuracy of a measure reliability

the consistency of a measure across some aspect, such as time

ValidityValidity

Four categories of validity internal external statistical conclusion construct

The Research ProcessThe Research ProcessSteps include

I. Problem Identification II. Research DesignIII. Data AnalysisIV. Interpretation and Presentation of Results

Problem IdentificationProblem Identification

Problem identification includes Concepts Hypotheses Variables

Research DesignResearch Design

Research design includes Type of Design Sampling Method Data Collection

SamplingSampling

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 CollectionData 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 AnalysisData Analysis

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

Data AnalysisData 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 & Interpretation & PresentationPresentation

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 Elements of the Scientific MethodMethod

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

ElementsElementsDirectional 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 ExperimentThe 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 ExperimentClassical Experiment

R O1 X O2 Experimental Group

R O3 O4 Control GroupWhere:

R = Random assignmentO1 and O3 are Pre-tests

O2 and O4 are Post-testsX = treatment (I.V.)

The classical experimental design can be diagramed as illustrated

Quasi-experimental Quasi-experimental DesignDesign

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 Quasi-experimental DesignDesign

O1 X O2 Experimental Group

O3 O4 Control GroupWhere:

O1 and O3 are Pre-tests

O2 and O4 are Post-testsX is the treatment (I.V.)

Evaluation ResearchEvaluation 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 ResearchBenefits 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 Application of Research ProcessProcess

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

SummarySummary

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