research methods Flashcards
Independant variable
In an experiment, it is the variable that it controlled and manipulated by the researcher.
Dependent variable
The variable that is measured by the researcher as a result of the manipulation to the IV.
Extraneous variables
These are generally unwanted variables that can have an impact on the relationship between the IV and the DV.
There are two types of extraneous variable: participant variables and situational variables
Participant variables
These relate to individual characteristics of a participant that may impact how they respond
Situational variables
These relate to things in the environment that may impact how each participant responds.
What are the 3 ways to reduce extraneous variables?
1) Standardisation
2) Random allocation
3) Double blind procedure
Standardisation
Keeping parts of the procedure the same so each participant experiences the same procedure.
Random allocation
Participants are randomly allocated to conditions rather than an experimenter choosing.
Double blind procedure
Neither the participants taking the test nor the experimenter know which condition the participants are in.
What are the 4 sampling techniques?
Random sampling
Stratified sampling
Volunteer sampling
Opportunity sampling
Random sampling technique
Every member of a population has an equal chance of being selected.
Strengths of random sampling technique
- It provides the best chance of an unbiased representative sample.
- Data more likely to be considered generalisable.
Weaknesses of random sampling technique
- It is time consuming
- A representative sample is not guaranteed; some participants may refuse to participate leading to a less representative sample.
Stratified sampling technique
A technique that ensures subgroups of a target population are proportionately represented in the sample.
Strengths of stratified sampling technique
- Ensures that the sample is completely representative as a cross-section of a target population.
-Useful if a small subgroup of the target population may be missed.
Weaknesses of stratified sampling technique
- It can be time consuming
- People can still refuse to take part
Opportunity sampling
Simply selecting those people that are available at the time.
Strengths of opportunity sampling technique
- Quick and convenient
- Saves time and effort
Weaknesses of opportunity sampling technique
- Can lead to biased sample since not every member of the target population will be around at the time of the study.
Define experimental designs
Experimental designs is how the participants are split into conditions.
Name the 3 types of experimental designs
1) Independent groups design
2) Repeated measures design
3) Matched pairs design
Independent groups design
Participants are split into conditions with each group tested in only one condition of the study.
Strengths of independent groups design
- It removes order effects as participants only complete one condition so the results are more valid
Weaknesses of independent groups design
- There may be individual differences between groups which can reduce the validity of the results.
- More participants are needed which can be time consuming to collect and test.
Repeated measures design
The same participants are used in all conditions.
Strengths of repeated measures design
- It compares the same participants so the changes are real which makes the results more valid.
- You don’t need as many participants which is less time consuming and makes them quicker to collect.
Weaknesses of repeated measures design
- Possibility of order effects. Participants’ performance is determined by the order that they complete the conditions. This reduces the validity of the results.
- Demand characteristics more likely as participants are more able to guess the aim.
Matched pairs design
Different participants in different conditions who are matched on a characteristic.
Strengths of matched pairs design
- It controls for individual differences which increases the validity of the results.
- Fair comparisons can be made between the groups as they are equally matched.
Weaknesses of matched pairs design
- It can be difficult and time consuming to match all participants.
Hypothesis
A hypothesis is a precise, testable statement of what the researchers predict will be the outcome of the study.
What are the two main ways of expressing a hypothesis?
1) Null hypothesis
2) Alternative hypothesis (experimental hypothesis)
Null hypothesis
States that there is no relationship between the two variables being studied, so the IV does not affect the DV.
Any results found are due to chance.
Alternative hypothesis
Also called an experimental hypothesis when the method of investigation is an experiment.
States that there is a relationship between the two variables being studied, so one variable will have an effect on the other.
What is the difference between a directional and non-directional hypothesis.
Directional hypothesis: A hypothesis that predicts the direction the results will go in.
Non-directional hypothesis: A hypothesis that predicts a difference/relationship will be found, but doesn’t specify what that difference/relationship will be.
What are the three types of experiments
1) Lab experiment
2) Field experiment
3) Natural experiment
Laboratory experiment
These normally take place in a controlled environment, such as a lab.
The researcher deliberately manipulates the IV while maintaining strict control over the extraneous variables through standardised procedures.
Strengths of laboratory experiments
- Strict controls and procedures mean other researchers can easily replicate lab experiments and check for reliability.
- High control over extraneous variables implies cause and effect can be studied without any influence from other unwanted variables, which helps with internal validity.
Weaknesses of laboratory experiments
- The artificial setting means participants might not demonstrate real-life behaviour, dramatically reducing ecological validity.
- Participants are invited to the experiment so they may display demand characteristics.
Field experiments
An experiment conducted in a natural environment, but there is still an IV that is manipulated by the researcher and a DV that is measured.
Strengths of field experiments
- Ecological validity is higher than in a lab experiment due to the ‘real world’ setting.
- There is cause and effect between the IV and DV, and some extraneous variables can be controlled.
Weaknesses of field experiments
- The researcher’s control over the environment s=is reduced in the real-world. Therefore, extraneous variables are more likely to confound the results and greatly reduce validity.
- Participants may be unaware of taking part so researchers may not have gained informed consent.
Natural experiments
When the change in the experiment is not brought about by the researcher.
It occurs in a real-life environment and has an IV and DV, but the researchers themselves do not manipulate the IV as it occurs naturally.
Strengths of natural experiments
- Great ecological validity
- Great generalisability
- Less bias from sampling and demand characteristics
- The environment in which participants are studies is real and naturalistic
Weaknesses of natural experiments
- The cause and effect of the IV and DV can be more easily affected by confounding variables.
- Participants cannot be randomly allocated to conditions of the IV, so participant variables may influence findings.
What are the two types of self report methods
Interviews and questionnaires.
Interviews
Interviews involve asking participants direct questions.
What are the three types of interviews
1) Structured
2) Semi-structured
3) Unstructured
Structured interview
The questions are already pre-made.
Semi-structured interview
Some questions are made before and some are made up.
Unstructured interview
The interviewer makes up questions on the spot.
Strengths of a structured interview
- It gathers a lot of information quickly which increases the validity.
- Very easy to replicate as every question is the same.
- It allows you to use the same questions again to see if you can find the same results which increases the reliability.
Weaknesses of a structured interview
- It might lead to gathering ‘superficial’ information and does not allow participants to respond freely.
Strengths of a semi-structured interview
- Allows a lot of in-depth information to be gathered because the researcher can ask the participants to elaborate on an answer. This increases the validity.
Weaknesses of a semi-structured interview
- It can be time-consuming asking additional questions and asking participants to elaborate.
Strengths of an unstructured interview
- A free-flowing conversation can occur so lots of data can be gathered which increases the validity of the results.
Weaknesses of an unstructured interview
- The interviewer needs training to encourage a free-flowing conversation.
Questionnaires
A set of pre-designed questions that the participant will answer.
These questions can be opened or closed
What do open questions in a questionnaire do
Allow participants to give a more detailed answer.
Qualitative data
What do closed questions in a questionnaire do
Allow the participant to give a more detailed answer
Quantitative data
Strengths of questionnaires
- Cheap to run
- Ethical as participant can choose whether to take part.
- Open questions are more valid as they are in depth
- The use of closed questions produces quantitative data which is reliable because it is easy to compare responses.
Weaknesses of questionnaires
- The participant may not answer truthfully (socially desirable response).
- Some participants may not respond to all questions which reduces the validity of the data.
What are the two types of data
Qualitative and quantitative.
Qualitative data
Qualitative data is mainly words.
Data that is descriptive, such as words or pictures.
Quantitative data
Quantitative data is mainly numerical.
Strengths of qualitative data
- Information is rich in detail which increases the validity of the results.
- It gives you a better insight into people.
Weaknesses of qualitative data
- Harder to compare with other data
- Can take longer to analyse
Strengths of quantitative data
- Data can be easily compared with other data.
- Data is easy to analyse.
Weaknesses of quantitative data
- Harder to get a true insight into people as data is not in depth.
- May not be valid.
Correlations
A correlation tells us whether there is an association or relationship between two variables.
A correlation is plotted on a scatter graph.
Positive correlation
As one variable increases, the other will also increase.
Negative correlation
As one variable increases, the other decreases.
No correlation
There is no relationship between the two variables.
Strengths of correlations
- Correlations are objective because they use quantitative data.
- Correlations open doors for new research.
Weaknesses of correlations
- Correlations can’t show cause and effect.
- Correlations lack detail as they only use quantitative data.
Observation
The process of watching and recording human behaviour.
Participant observation
The observer takes part in the activity to be observed
Non-participant observation
The observer does not take part in the activity to be observed.
Covert observation
The participants are unaware that they’re being observed.
Overt observation
The participant knows that they’re being observed
Naturalistic observation
The observation is in a natural setting
Structured observation
The observation is at a laboratory or controlled environment staged by the observers to see what happens.
Reliability
Whether the research can be repeated or replicated.
Researchers can ensure that the research is reliable by controlling the variables, including extraneous variables.
This can be done using a standardised procedure and scientific measures which produce quantitative data, as this is easier to compare for consistency.
Validity
Whether the study reflects the truth.
Researchers can ensure validity by using a natural environment and tasks which means that participants are less likely to show demand characteristics and provide socially desirable responses.
Internal validity
Whether the measures used in a test genuinely test what they are designed to test.
External validity
Whether the findings are generalisable to the target population.
Most ethical observation
Overt observation because the participants are aware they’re being observed and can choose whether to take part.
Least ethical observation
Covert observation because participants are unaware that they’re being observed and so cannot provide consent.
Most reliable observation
Structured observation because the event is planned and staged which means there can be more control over variables.
Least reliable observation
Natural observation because this is in a natural setting which means it is harder to control the variables especially extraneous variables.
Most valid observations
Natural and covert observations, because it is a natural setting that the participants are familiar with and they’re unaware of being watched.
This means that the study has ecological validity because the participants are more likely to show truthful behaviour.
Least valid observations
Structured and overt observations because the participants are aware that they’re being observed and might show demand characteristics.
Also, artificial settings reduce the ecological validity of the observation.
Case studies
An in-depth study of one participant or a group of participants. Often participants are studies because the sample is unique in some way.
Strengths of case studies
- Case studies are rich in about people you want to study, which increases the validity of the data.
- Case studies have high ecological validity, as often in a natural setting.
Weaknesses of case studies
- Case studies are time consuming especially if a researcher is collecting data over many years.
- It is hard to generalise the findings as only a small group of participants are studied which do not represent the wider population.
- Case studies cannot be repeated to check the reliability of the findings, as every individual studied is unique.
Consent
Participants give their permission to take part.
Debrief
Participants are informed about the true aim of the research, after the investigation.
Confidential
Participants are kept anonymous.
Deception
Participants are not lied to.
Withdraw
Participants can leave the research at any time.
Protection from harm
Participants are not affected physically or psychologically.
