Week 1c
Lecture 3: Research Strategies
Goals of Developmental Psychology
To Describe: to observe human behaviour to describe how humans change overtime and describe trends and individual variations
To Explain: to explain and try to understand why humans develop as they typically do, and why some people turn out different than others
To optimize development: apply what eve learned in hoping to help individuals in developmental stages in life \n
Scientific Method
- a series of steps taking by researchers to assure observations are accurate/verifiable
- researchers must be objective and allow their observations and data to decide the merits of the theorizing
- Steps involved
- reasoning, systematic observations and communication
- choose a question to be answered
- formulate a hypothesis regarding the question
- develop a method for testing the hypothesis
- use the data yielded by the method to draw a conclusion regarding the hypothesis
Theory
- a set of concepts and propositions designed to organize, describe and explain an existing set of observations
Hypothesis
- a specific assumption or prediction - must be testable to determine accuracy
**Theories should be parsimonious, falsifiable, and general ideas
Criteria for the scientific method:
- all are necessary in research
- Objectivity: scientific knowledge may not be distorted by researcher's preconceptions/biases \n Reliability: extent to which the measuring instruments give consistent results - over time and across observers \n Replicability: if researchers used similar procedures, they would yield similar results Validity: extent to which the measuring tools accurately reflect the intended purpose
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Types of Research
Basic research
- conducted to advance general knowledge
Applied research
- designed to solve practical problems
Action research
- designed to provide data that can be used in social policy making
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Methods of Data Collection:
Observation
- naturalistic - observing individuals in their natural environment during everyday life;
- controlled - observing individuals in a formal (labt setting
Self-report
- Interviews
- structured - all participants are asked the same questions
- clinical - questions are tailored to each individual, each question determined by the preceding answers
- Questionnaires: participants respond to standard questions using pencil & paper method
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Experiments
- a change is introduced, and the effect is measured; experimental group is exposed to treatment, control group is not exposed to treatment
- Dependent Variable: the variable that remains constant
- Independent Variable: the variable that is manipulated to reach treatment goals
Quasi-Experiment
- measures the impact of a naturally occurring event
- ethical considerations prevent experimental control
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Ecological Validity: when the experimental settings diverge too far from natural environment, behavior is often modified
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Longitudinal Research Design:
- The same participants are observed or interviewed over a long period of time (can be months-years
- same people at different ages
- can test the development and stability of attributes
- Disadvantages: Practice effect - participants get used to the testing method, attrition - loss of participants over time, cross-generational effect - an event impacting a population (cohort effect, eg. People who lived through 911
Cross-Sectional Research Design:
- Participants from different age groups are observed or studied at the same point in time (less time consuming than longitudinal
- different people at different ages observed at a different point in time
- Disadvantages: cohort effects - differences in age groups may impact results
Microgenetic Research Design:
- Intensely observing development over short periods, especially when children are on the verge of change
- Disadvantages: limited to changes occurring over short periods of time
Cohort Sequential Research Design:
- Combines longitudinal and cross-sectional approaches by studying several cohorts over a period of time
- Disadvantages: similar to the disadvantages for the two it combines
Triangulation
- when a researcher combines 2+ techniques to confirm their conclusions
Ethics in research: must get informed consent, provide freedom from harm, and confidentiality