Child Development Laura E Berk 8 th edition

Child Development Laura E. Berk 8 th edition Chapter 2 Research Strategies This multimedia product and its contents are protected under copyright law. The following are prohibited by law: Any public performance or display, including transmission of any image over a network; Preparation of any derivative work, including the extraction, in whole or in part of any images; Any rental, lease, or lending of the program. Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Hypothesis A prediction often drawn from a theory. Research can: – Test a prediction of one theory against that of another – Test a prediction of one theory – Start with a research question, if there is no theory Photodisc Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Why Should We Learn About Research Strategies? Helps us separate dependable information from misleading results. Individuals who work with children may be in a unique position to build bridges between research and practice. Stockbyte Royalty Free Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Systematic Observation Naturalistic Observation Structured Observations In the “field, ” or natural environment, where behavior happens Laboratory situation set up to evoke behavior of interest All participants have equal chance to display behavior Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Collecting Systematic Observations Event Sampling Time Sampling Observer records all instances of a particular behavior during a specific time period. Observer records whether certain behaviors occur during a sample of short time intervals. Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Limitations of Systematic Observation Observer Influence – Participants may react in unnatural ways. – Can be minimized Observer Bias Corbis Royalty Free – Observers record what they expect, rather than what really happens. – A serious danger Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Interviews Clinical Interview Structured Interview Flexible, conversational style Probes for participant’s point of view Each participant is asked same questions in same way May use questionnaires, get answers from groups Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Limitations of Clinical Interviews Accuracy of participants’ expressions Distortions in participants’ – Recall – Judgments Flexibility make responses too varied Photodisc Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Psychophysiological Methods Measures of autonomic nervous system activity – Heart rate, blood pressure, respiration, pupils, stress hormones Rubber. Ball Productions Royalty Free CD Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Methods of Measuring Brain Functioning Electroencephalogram (EEG) Event-related potentials (ERPs) Functional magnetic resonance imaging (f. MRI) Position emission tomography (PET) Near-infrared optical topography (NIROT) Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Functional magnetic resonance imaging (f. MRI) AP/Wide World Photos © Scott K. Holland Copyright

Near-infrared optical topography (NIROT) NIROT is limited to examining the functioning of the cerebral cortex. Can be used on very young babies as they sit on their parent’s lap. Courtesy of Gentaro Taga, University of Tokyo Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Memory Impairments in Infants of Diabetic Mothers: Findings of ERP Research Charles Nelson’s research using ERPs to assess young infants’ memory performance showed a diabetic pregnancy places the fetus at risk for lasting memory deficits as a result of iron depletion in critical brain areas. Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

ERPs recorded over the left temporal lobe as 8 -month old infants of diabetic mothers and controls viewed familiar and novel objects. Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Clinical/Case Study Method Brings together a wide range of information on one child – Interviews – Observations – Test scores – Psychophysiological measures Family Life Royalty Free CD Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Ethnography Descriptive, qualitative technique Goal is to understand a culture or social group Participant Observation – Researcher lives in community for months or years Photodisc Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Immigrant Youths: Amazing Adaptation Academic Achievement and Adjustment – Very high outcomes, especially among Chinese, Filipino, Japanese, Korean, and East Indian youths. Family and Community Influences – Parents emphasize trying hard and the value of education. Children view success at school as a way of repaying their parents for their sacrifices. Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Reliability and Validity Reliability Validity Consistency, repeatability of a measure How accurately the measure captures the characteristics the researcher is trying to study – Inter-rater – Test-retest – Internal validity: study conditions – External validity: generalizability Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Correlation Coefficients Magnitude Direction Size of the number between 0 and 1 Closer to one (positive or negative) is a stronger relationship Indicated by + or sign Positive (+): as one variable increases, so does the other Negative (-): as one variable increase, the other decreases Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Correlations Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Examples of Correlation Coefficients Copyright © 2009 Pearson Education, Inc. Publishing as Allyn &

Independent and Dependent Variables Independent Dependent Experimenter changes, or manipulates Expected to cause changes in another variable Experimenter measures, but does not manipulate Expected to be influenced by the independent variable Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

An Example of a Laboratory Experiment Copyright © 2009 Pearson Education, Inc. Publishing as

Random Assignment Photodisc Avoiding Confounding Variables – Researchers use unbiased procedure to assign participants to treatment conditions – Sometimes combined with matching participants on key characteristics Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Modified Experiments Field Experiment Natural Experiment Use rare opportunities for random assignment in natural settings Quasi-experiment Compare differences in treatment that already exist Groups chosen to match characteristics as much as possible Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

An Example of a Natural Experiment Copyright © 2009 Pearson Education, Inc. Publishing as

Can Musical Experiences Enhance Intelligence? Copyright © 2009 Pearson Education, Inc. Publishing as Allyn

Designs for Studying Development Longitudinal Same participants studied repeatedly at different ages People of differing ages all studied at Cross-sectional the same time Sequential Microgenetic Same groups of different-aged people studied repeatedly as they change ages Same participant studied repeatedly over a short period as they master a task Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Longitudinal Design Advantages Permits study of common patterns and individual differences in development and relationships between early and later events and behaviors. Problems Age-related changes may be distorted because of biased sampling, selective attrition, practice effects, and cohort effects. Theoretical and methodological changes in the field can make findings obsolete. Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Cross-Sectional Design Advantages Efficient Not plagued by selective attrition, practice effects, or theoretical and methodological changes in the field Problems Does not permit study of individual developmental trends Age difference may be distorted because of cohort effects Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Sequential Design When the design includes longitudinal sequences, permits both longitudinal and cross-sectional comparisons Reveals cohort effects Permits tracking of agerelated changes more effectively than the longitudinal design May have the same problems as the longitudinal and crosssectional strategies, but the design itself helps identify difficulties Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Example of a Sequential Design Copyright © 2009 Pearson Education, Inc. Publishing as Allyn

Microgenetic Design Offers insights into how change occurs Requires intensive study of participants’ moment-by-moment behaviors The time required for participants to change is difficult to anticipate Practice effects may distort developmental trends Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.

Children’s Research Rights Protection from harm Informed consent Privacy Knowledge of results Beneficial treatments Corbis Royalty Free Copyright © 2009 Pearson Education, Inc. Publishing as Allyn & Bacon.