non - experimental research - survey methods Flashcards
key issues for non experimental research
Third variable problem: an observed relation between two variables may be the result of some third, unspecified variable.
Direction of causation problem: a correlation does not indicate which variable is the cause and which is the effect.
Nonprobability sampling
Convenience sampling – researcher requests volunteers from a group of people who meet the general requirements of the study
Snowball sampling – previous participants recruit additional participants through their network
Purposive sampling – researcher targets a particular group of individuals in a nonrandom way
Quota sampling – proportions of some subgroups are the same as subgroup proportions in the population but nonrandomly selected
Overview
- Using surveys to measure subject variables
- Defining and evaluating constructs
- Using surveys in correlational designs
Designing & evaluating survey questions
Subject variables
- Subject variables are attributes that vary across individuals and situations.
Subject variables can be studied with a range of methods, including survey methods.
Survey methods
- A survey is a descriptive method in which participants are asked a series of questions or given statements to rate.
- Survey methods can measure almost anything that can be observed, evaluated & reported accurately.
Survey methods can be especially useful for measuring psychological dimensions that are difficult to induce or observe, including attitudes, beliefs & behaviours.
fundamentals of measurement
validity refers to the accuracy of research
reliability refers to the consistency of research
surveys in correlational designs
TV habits of 875 3rd graders in Hudson Valley NY evaluated with three questions in 286-item home interview
Each child rated every other child in his classroom on 10 aggressive behaviors
Strong positive relationship between violence rating of favorite programs, whether reported by mothers or fathers, and peer-rated aggression of boys
Ten years later Eron & colleagues evaluated TV habits & aggression in 427 of the original 875 children. They reported a significant cross-lagged correlation between violent TV in 3rd grade and aggression 10 years later – but only for boys. Partial correlations supported their interpretation that TV violence causes aggression.
tried to control for a third variance using partial correlations
correlation and causation
- When survey research methods are used in correlational designs, they are susceptible to problems of causal inference.
- Direction of causation problem
- Third variable problem
- Longitudinal designs help to address direction of causation.
In some surveys the third variable problem can be addressed with statistical techniques.
designing survey questions
There are standard procedures for developing surveys & questionnaires to ensure that instruments are valid & reliable.
The most fundamental issue is whether your survey or questionnaire is fit for purpose:
Given your aim, are you measuring the right thing?
Survey research depends on people being able to observe, evaluate & report the target variable accurately.
subjectivity and objectivity
approaches to measurement - experience, behaviour, performance
Surveys & questionnaires may seem simple, but they involve complex cognitive processes
- Understanding the question
- Retrieving relevant information
- Forming a judgment
- Formatting the judgment to fit response alternatives
Editing the answer
Designing survey questions
The wording of survey questions is important
- Avoid ambiguity
- Avoid leading questions
- Don’t ask two questions in one item
- Aim for simplicity
- Use complete sentences
Avoid abbreviations, slang & jargon
Evaluating survey questions
The legacy of introspectionism has influenced how survey questions are evaluated.
Just as Dallenbach and his colleagues reported on their experience on completing a task, we can ask participants to report on their experience whilst completing a survey.
Cognitive interviews
Cognitive interviews are an important tool for evaluating survey questions.
* Ronald Fisher & Edward Geiselman developed the cognitive interview technique to increase the accuracy of eyewitness testimony.
* Basic principle is to match the context of testimony to the context of the event to be remembered.
Cognitive interviews are useful for pilot study of survey questions.
Psychometric evaluation
- The underlying factor structure of surveys can be evaluated with factor analysis.
- Factor analysis is a multivariate analysis in which a large number of variables are correlated with each other.
Factor analysis allows researchers to identify which survey questions or items cluster together to form a scale.