research methods Flashcards
aims meaning
the aims of a study is what the purpose is of a piece of research. for example, to test if age affects memory
hypothesis definition
the prediction of what the research will be
alternative hypothesis meaning
a testable statement which predicts how one variable will affect another. it is a statement which predicts a difference between conditions in an experiment or a correlation between two variables
null hypothesis
states that there is no relationship between the two variables being studied. There will be no changes in the dependent variable due to manipulation of the independent variable. It states results are due to chance and are not significant in terms of supporting the idea of being investigated
non directional hypothesis
a two tailed hypothesis predicts that the independent variable will have an effect on the dependent variable, but the direction of the effect is not specified. it just states that there will be a difference.
eg. there will be a difference in how many numbers are correctly recalled by children and adults
directional hypothesis
a one tailed hypothesis predicts the nature of the effect of the independent variable on the dependent variable. it predicts in which direction the change will take place.
eg. adults will correctly recall more words than children
random sampling
each member of the target population has an equal chance of being selected. for example using random number generator, or picking names out of a hat
pros of random sampling
there is no bias
simple
cons of random sampling
large random sampling may be impractical, complete list of the population may be unbelievable
systematic sampling
a participant is selected in a systematic way, for example, selecting every 10th person from the electoral roll. this is decided through a sampling frame, where a list of the target population is put in order
pro of systematic sampling
lower probability of contaminating data
cons of systematic samping
under representation of particular patterns, grater risk of data manipulation
stratified sampling
the total population is divided into smaller groups or strata to complete the sampling process
pros of stratified sampling
you obtain reasonable precise estimates for all subgroups related to your research questions
cons of stratified sampling
the selection of appropriate strata for a sample may be difficult
opportunity sampling
participants are selected from whoever is most easily available. For example, standing in the street one afternoon and approaching passers-by to see if they want to take part
pros of opportunity sampling
quick way and easy of choosing participants
cons of opportunity sampling
may not provide a representative sample, could be biased
volunteer sampling
participants put themselves forward to take part in a study. For example, a newspaper or internet advert is placed asking for volunteers, and people respond agreeing to take part
pros of volunteer sampling
not time consuming, easily minimal effort is required
cons of volunteer sampling
volunteer bias, cannot be generalised
extraneous variables
an unwanted factors in a study that, if not accounted for, could negatively affect the data subsequently collected. such factors potentially prevent researchers from finding a direct casual effect between the manipulated independent variables and measured dependent variables set out in an investigation
cofounding variables
a third variable in a study examining a potential case-and-effect relationship
participant variable - minimizing differences between participants (eg. their stage of development such as age, or ability such as IQ)
situational variable - control of the setting where the experiment takes place (eg. keeping light, sound and temperature levels consistent)
demand characteristics
all the clues in an experiment which convey to the participant the purpose of the research. demand characteristics can change the results of an experiment if participants change their behaviour to conform to expectations
investigator effects
when a researcher unintentionally, or unconsciously influences the outcome of any research they are conduction
randomisation
a way of controlling for the effects of extraneous/cofounding variables. it greatly decreases systematic error, so individual differences in responses or ability are far less likely to consistently affect results
standardisation
the process in which procedures used in research are kept the same. this therefore means that the investigation is far. for example, the instructions given to the participants are all the same and given in the same way, time etc.
single blind
when the participant does not know the aim of the study. this helps reduce the possibility of demand characteristics from affecting the results.
double blind
when the investigator who deals with the participants also does not know the aim of the study. This helps reduce the chance of investigator effects, as the investigator will not unconsciously communicate the aim of the participants.
control group
used for the purpose of comparison, often when testing the effects of a drug. for example, one group of participant (experimental group) will be given the real drug, another group will be given placebo. this can allow the researcher to directly compare the results of the two groups.
ethical issues
considerations that researchers need to consider before during and after the research is conducted. Ethical issues take into consideration the welfare of the participants, the integrity of the research and the use of the data
deception
deception = when information is deliberately withheld from participants or they are knowingly mislead.
It is unethical if broken as it prevents participants from giving fully informed consent which means that they might be taking part in research that goes against their views of beliefs.
how to deal: at the end of the study, the participants should be fully debriefed and told the true aim and nature of the research. At this point, the participants should be given the right to withdraw the publication of their results. The contact details of the experimenter should be given if participants have any further questions or queries.
right to withdraw
right to withdraw = participants have the right to withdraw (remove themselves or their data from the study) at any stage. This includes after the research has been conducted, in which case the researcher must destroy any data or information collected.
It is unethical is broken as participants who are not given the right to withdraw may feel unnecessary or undue stress and are therefore not protected from harm.
how to deal: at the end of the study the participants should be fully debriefed and told the true aim and nature of the research. At this point, the participant should be given the right to withdraw the publication of their results. The contact details of the experimenter should be given if participants have any further questions or queries.
informed consent
informed consent = when someone consents to participate in research, their consent must be fully informed which means the aims of the research should be made clear before they agree to participate.
it is unethical is broken as ack of informed consent may mean the participant is taking part in research that goes against their wishes of beliefs. It is possible that the participant may have felt obliged to take part or even coerced into it, especially if they are not fully informed.
how to deal: at the end of the study, the participants should be fully debriefed and told the true aim and the nature of the research. At this point the participant should be given the right to withdraw the publication of their results. The contact details of the experimenter should be given if participants have any further questions or queries.
privacy
privacy = privacy is the right of individuals to decide how information about them will be communicated to others
A skilled researcher may obtain more information from a participant than they wish to give which could be an invasion of privacy and the participant may later feel ashamed or embarrassed.
how to deal: The participant should be provided with fully informed consent and the right to withdraw at any stage. Furthermore, the researcher should explain to participants the ways in which their information will be protected and kept confidential
confidentiality
confidentiality = where a participant’s personal information is protected by law under the Data Protection Act both during and after the experiment.
it is unethical if broken as a person’s details or data may be used by other parties against the participants wishes.
how to deal: participants are provided with a fake name, number or initials to protect their identity and assure anonymity. They should not be identifiable by any person, institution, or organisation.
what is laboratory experiment
conducted in a highly controlled environment. The IV is manipulated to see the impact on the DV, whilst the effects of other variables are minimised as far as possible. For example, giving researchers lists of words to remember, giving them another task to prevent rehearsal, then testing their recall of the information
strength of laboratory experiment
extraneous variables are closely controlled, meaning the IV is likely to have affected the DV, increasing the internal validity of the study. Research can be easily repeated as there will be a controlled, standardised procedure, increasing the reliability of the results
weakness of laboratory
artificial nature of the set-up means that the results may not reflect ‘real-life’ behaviour, so reducing the external validity of the study. participants know they are being tested so many change their behaviour showing demand characteristics
what is a field study
a study that is conducted outside the laboratory in a ‘real world’ setting
strength of field study
higher mundane realism therefore higher external validity. the behaviour occurs in its natural environment, so often participants wont know they are being studies, so demand characteristics are less of an issue.
weakness of field study
harder to control extraneous variable, so harder to know if the IV has affected the DV. If participants are unaware they are being studies this raises ethical issues (lack of informed consent)
natural experiment
the experimenter studies the effects of a naturally occurring IV. Participants may still be studied in a lab-type setting to see the effects, but the IV is not manipulated by the researcher.
strength of natural experiment
high external validity as the IV is naturally occurring (not manipulated). The effects can be tested of factors that could not be manipulated by the researcher. It is ethical because the researcher is not forcing anything.
disadvantage of natural experiment
even less control of extraneous variable than field experiments. naturally occurring IVs may be rare, so studies cant be repeated. participants cant be randomly allocated to conditions, introducing the possibility of bias.
what is a quasi experiment
the IV is based on an existing difference between people. For example, gender differences in attitudes towards food.
advantages of quasi experiment
can be tested under controlled conditions, increasing the scientific credibility of the research.
disadvantage of quasi experiment
participants couldnt be randomly allocated to conditions, introducing possible cofounding variables
qualitative data
data in the form of words, which is rich and detailed. often this is produced from case studies, and unstructured interviews and observations
quantitative data
data in the form of numbers, which is often produced from lab experiments or closed questions
primary data
data that has been collected by the researcher for the purposes of the study
secondary data
data collected by someone other than the researcher, for example census information. the researcher makes use of this as part of their study, but the information was not collected for the purpose of that study.
nominal measurement
the data can only be categorized
you can categorize your data by labelling them in mutually exclusive groups, but there is no order between categories
eg. city of birth, gender, ethnicity
ordinal measurement
the data can be categorized and ranked
you can categorize and rank your data in an order
eg. top 5 Olympic medallists, language ability
interval measurement
the data can be categorized, ranked, and evenly spaced
you can categorize, rank and infer equal intervals between neighbouring data points, but there is no true zero point.
eg. test scores, temperature
ratio measurement
the data can be categorized, ranked, evenly spaced and has a natural zero
you can categorize, rank and infer equal intervals between neighbouring data points, and there is a true zero point
eg. height, age, weight
