Unit 8
Program improvement or appraisal Assessing the value of a program Measuring the efficacy of particular components of a program Meeting accountability requirements. Data used for decisions about whether to maintain a program, advance it, introduce comparable programs elsewhere, allocate resources among rival programs, or accept or reject a program approach or hypothesis.
Head Start or Title I – US Dept of Education Math curriculum in one district Four Questions of Program Evaluation (Posavac & Carey, 1997) ◦ Needs Is an agency or organization meeting the needs of the people it serves? ◦ Process How is a program being implemented (is it going as planned)? ◦ Outcome Has a program been effective in meeting its stated goals? ◦ Efficiency Is a program cost-efficient relative to alternative programs?
Evaluators use many of the same qualitative and quantitative methodologies used by researchers in other fields. Primary purpose of evaluation is to provide information for decision-making about particular programs, not to advance more wide-ranging knowledge or theory. ◦ Evaluation is more client-focused than traditional research, in that evaluators work closely with program staff to create and carry-out an evaluation plan that attend to the particular needs of their program.
Evaluation serves to aid in a program's development, execution, and improvement by examining its processes and/or results Assessment measures individuals or group's performances by measuring their skill level on a variable of interest (e.g., reading comprehension, math or social skills).
An experiment is any study in which a treatment is introduced. ◦ A new method of teaching, different behavioral intervention, A non-experimental study does not introduce a treatment. ◦ Comparing opinions from natural groups
Any study in which a treatment is introduced is an experiment. Control: Researchers investigate the effect of various factors one at a time in an experiment. An experiment has at least one independent variable and at least one dependent variable. A true experiment involves random assignment of participants to treatment groups.
An intervention or a treatment is implemented. True experiments have a control group ◦ Two groups have the same tx, except for the independent variable of interest. In true experiments, confounding variables are well controlled by the experimenter. ◦ Random assignment
Experimental Group: group receiving treatment Control Group: group not receiving treatment ◦ Represents expected results for experimental group if no treatment is given ◦ Represents population before treatment or if no treatment.
Concerns about usefulness of results ◦ School board presidents and government and business leaders are hesitant to allow “poking around”. Access to participants ◦ “Wait list” ◦ Random assignment
Potential causes for a research finding. Researchers must rule out these alternative explanations. Eight confound categories - “threats to internal validity”: ◦ history ◦ maturation ◦ testing ◦ instrumentation ◦ regression ◦ subject attrition (mortality) ◦ selection ◦ interactions with selection
When there is no comparison group in the study, the following threats to internal validity must be considered: ◦ history, maturation, testing, instrumentation, regression, subject mortality, selection When a comparison group is added, the following threats to internal validity must be considered: ◦ selection, interactions with selection
Because of contamination, expectancy effects, and novelty effects, researchers may have difficulty concluding whether a treatment was effective.
Contamination: Happens due to communication about the experiment between groups of participants. Three possible outcomes of contamination: ◦ resentment: some participants’ performance may worsen because they resent being in a less desirable condition; ◦ rivalry: participants in a less desirable condition may boost their performance so they don’t look bad; and ◦ diffusion of treatments: control participants learn about a treatment and apply it to themselves.
Expectancy Effects: researcher unintentionally influences the results of an experiment. ◦ Researchers can make systematic errors in their interpretation of participants’ performance based on their expectations. ◦ Researchers can make errors in recording data based on their expectations for participants’ performance.
Novelty Effects: This refers to changes in people’s behavior simply because an innovation (e.g., a treatment) produces excitement, energy, and enthusiasm ◦ Hawthorne effect: performance changes when people know “significant others” (e.g., researchers, company bosses) are interested in them or care about their living or work conditions.
GOVERNMENT WARNING: ◦ (1) According to the Surgeon General, women should not drink alcoholic beverages during pregnancy because of the risk of birth defects. ◦ (2) Consumption of alcoholic beverages impairs your ability to drive a car or operate machinery, and may cause health problems. The U.S. National Institute on Alcohol Abuse and Alcoholism funded the Alcohol Research Group to conduct a series of cross-sectional surveys in the United States and Ontario, Canada (Greenfield et al., 1999).