introduction to operations research

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INTRODUCTION TO OPERATIONS RESEARCH Niranjan Saggurti, PhD Senior Researcher Scientific Development Workshop Operations Research on GBV/HIV AIDS 2014, Melbourne, July 22, 2014

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Introduction to Operations research. Niranjan Saggurti , PhD Senior Researcher Scientific Development Workshop Operations Research on GBV/HIV AIDS 2014, Melbourne, July 22, 2014. Goal of Operations Research. - PowerPoint PPT Presentation

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Page 1: Introduction to  Operations research

INTRODUCTION TO OPERATIONS RESEARCH

Niranjan Saggurti, PhDSenior Researcher

Scientific Development WorkshopOperations Research on GBV/HIV

AIDS 2014, Melbourne, July 22, 2014

Page 2: Introduction to  Operations research

Goal of Operations Research

• To increase the efficiency, effectiveness and quality of services delivered by providers

• To increase the availability, accessibility and acceptability of services desired by clients

• To use information collected to strengthen provision of services

Page 3: Introduction to  Operations research

Operations Research Process It involves 5 critical steps:1. Problem identification and diagnosis 2. Strategy selection 3. Strategy testing and evaluation 4. Information dissemination 5. Information utilization

Page 4: Introduction to  Operations research

Categories of Operations Research Studies • Exploratory or Diagnostic Studies

Problem isn't known

• Field Intervention Studies Program approach not known

• Evaluation Studies Impact not known

• Cost-Effectiveness Studies Cost and effectiveness not known

Page 5: Introduction to  Operations research

Steps in Operations Research

Page 6: Introduction to  Operations research

Problem Identification

• Is it an important problem? • To whom is it important?• How can the problem be addressed

by the program? • What health improvements will result

from solving this problem?

Page 7: Introduction to  Operations research

Is the Problem Researchable

• Do I need to do research to solve the problem?

• Can the problem be corrected by common sense and experience?

• Do I have enough time, money and qualified persons to do research?

• Will decision makers listen to research results?

• What ethical issues need to be considered?

Page 8: Introduction to  Operations research

Stating an OR Problem

• Describe the problem in terms of health issues facing the specified population(s)

• Describe the nature and extent of the problem

• Identify other program strategies that have been tried to solve similar problems

• Restate the problem as a question to be answered through research

Page 9: Introduction to  Operations research

Strategy to Solve the Problem

• Once an operations research problem has been identified, defined and justified a range of strategies for solving the problem can be suggested.

Page 10: Introduction to  Operations research

Choosing a Strategy to test Feasibility

• Can the program afford it?• Can it be easily implemented? • Will it be effective? • Is there enough time to test it?• Do the staff and managers want to

test it?

Page 11: Introduction to  Operations research

Research Hypotheses, Objectives and Variables

Page 12: Introduction to  Operations research

Hypotheses

• Hypotheses is a statement that specifies the expected relationship between two or more variables that can be tested through collecting information and conducting experiment

E.g. Contraceptive use will be higher in villages where the fieldworker is married than in villages where the field worker is unmarried.

Page 13: Introduction to  Operations research

Objectives

• Objectives relate to reasonable and expected contributions of the study to broad social, economic or health concerns

• An ultimate objective is that the study will provide program administrators/ mangers and policy makers with information that can be used to improve service delivery activities or reformulate policy.

Page 14: Introduction to  Operations research

Independent variables

• Programmatic factors that can be manipulated

• Strategy being tested • The “cause”

Page 15: Introduction to  Operations research

Dependent Variables

• Characteristics we expect to change • Outcomes and/ or impact being

measured • The “effect”

Page 16: Introduction to  Operations research

Types of Study Designs to Test Hypotheses

Page 17: Introduction to  Operations research

True and Quasi-Experimental Design

Quasi-Experimental Design • Does not use random assignment • Open to many threats to validity • At best, only suggestive of causality

True Experimental Design • Uses random assignment • Protects against threats to validity • Demonstrates causality

Page 18: Introduction to  Operations research

Units of Study in Operations Research

• Individuals: clients, providers, the general public

• Groups: facilities (e.g. clinics), villages, districts

Note: When unit of study is a group, the group not the individual must be used as variance measure

Page 19: Introduction to  Operations research

Symbols

= Between groups not randomly assigned

RAExperimental Group

Control Group= Random Assignment of

cases to the groups

= The passage of time

= Intervention

= Observation

= A single group of subjects

X

O

X and O in a row

- - - - - - - - - - - - - - -

Page 20: Introduction to  Operations research

Classic Experimental Design

RAExperimental Group O1 X O2

Control Group O3 O4

Time

Page 21: Introduction to  Operations research

Pretest-Posttest Non-Equivalent Control Group Design

• No random assignment

Experimental Group O1 X O2

Control Group O3 O4

Time

- - - - - - - - - - - - - -

Page 22: Introduction to  Operations research

Time Series Design

• Repeated measures on the same group over time

• No control or comparison group

ExperimentalGroup O1 O2 O3 X O4 O5 O6

Time

Page 23: Introduction to  Operations research

Non-Experimental Designs• Case StudyExperimental Group

X O1

• One Group Pre-test/Post-testExperimental Group

O1 X O2

Time

Time

Page 24: Introduction to  Operations research

Good Design to Study Integrated Services

PROGRAM XYES

PROGRAM XNO

PROGRAM YYES

X+Y Y

PROGRAM YNO

X 0

Page 25: Introduction to  Operations research

Overview of Data Collection Methods • Quantitative methods describe what

people do (e.g, how many people are using IUD). Need a lot of people for statistical analysis if the rates of usage is low.

• Qualitative methods explore why people think and behave as they do (e.g., why difficult to use IUD). Need a lot of in-depth information from few people.

Page 26: Introduction to  Operations research

Ensure Results are Used

• Plan a utilization strategy that anticipates what actions are needed to change the way services are currently implemented

• Allow sufficient time, funds and qualified persons to do a good job