Research methods Flashcards
Independent variable
The groups in the experiment. What the researcher manipulates (the cause)
Dependent variable
The researcher measures this (the effect)
What does operationalising mean?
Being specific about what you are measuring and how it will be measured. Needs to be done for both IV and DV
What is a hypothesis?
Where the researcher will make a clear testable prediction about the outcome of the investigation
What is a 1 tailed or “directional” hypothesis?
When the researcher predicts which condition will be higher
What is a 2 tailed or “non directional” hypothesis?
When the researcher predicts there will be a difference between the conditions
What is a null hypothesis?
when the researcher predicts there will be no significant difference between the conditions
What is an extraneous variable?
An additional variable that may have an effect on the result (DV)
What are the 4 Types of extraneous variables?
Participant - Characteristics of the p
Situational - External environmental factors
Researcher - Researcher bias
Demand characteristics - Participant changing behaviour to fit the aims of experiment
Quantitative data strengths and weaknesses:
+ More objective
+ Easier to compare and manipulate
- can lack meaning/validity
Qualitative data strengths and weaknesses:
+ Has more meaning/validity
- More subjective
- Harder to compare and manipulate
What is primary data?
Data collected by researcher for the purpose of specific investigation
What is secondary data?
Data that has been collected previously not by the researcher conducting the current investigation
Strengths and weaknesses of primary data:
+ You can control your own procedure
+ You can be more sure of the validity
- Small sample
- Need to consider ethical guidelines
Strengths and weaknesses of meta analysis:
+ increased sample size
+ don’t need to consider ethical guidelines
+ can overcome issues of population validity
- Cannot choose exactly what to study
- Publication bias
- Validity of the original studies not detemined
- Mixing studies not measuring the same thing
What is publication bias?
The failure to publish the results of a study on the basis of the direction or strength of the study findings
Mean definition and +/-
The arithmetic average
+ Most sensitive, extracts most info from scores because all raw data is included
- Can be greatly affected by outliers
Median and +/-
The middle value when scores are arranged in descending order
+ It is not effected by outliers
- Does not take all raw scores into account
Mode and +/-
The most frequently occurring value
+ Only measure possible when data is not numerical (nominal)
- Mode is not applicable in data sets without modes
What is standard deviation?
Most powerful measure of dispersion, tells us how far on average each score is from the mean
+ uses all data points
What are Independent groups?
Participant divided into 2 groups, each do experimental task with the IV set for condition 1 or 2. And compare each groups results.