Strength of opportunity sampling? | Quick and practical |
Strength of opportunity sampling? | Quick and practical |
What is stratified sampling? | When there are subgroups in the target population and people are randomly selected from it. Ensure that it is proportionally representative |
What is stratified sampling? | When there are subgroups in the target population and people are randomly selected from it. Ensure that it is proportionally representative |
What is systematic sampling? | Picking the sample from a nth number of people in a predetermind system. (eg every 10th person) |
A strength of systematic sampling? | Its an objective method of choosing participants for an experiment, this means that is not opened to bias. |
A weakness of systematic sampling? | It is time consuming and participants that are selected might choose not to take part |
Weaknesses of naturalistic observation? | No control over extraneous variables |
Weaknesses of a field experiment? | Less control: more extraneous variables are likely in a natural environment
Ethics: |
Strength of random sampling? | Equal chance to be selected and sample will mostly likely be representative |
What is an aim of a study? | The purpose of the study and what you are trying to achieve |
What is a null hypothesis? | Where there is no relationship between the 2 variables that are being studied. There will be very little effect of your IV and DV, any difference would be down to chance. |
What is a directional (one-tailed) hypothesis? | When you predict the direction of the result. Eg. The higher the temperature, the more the person will sweat. Key words: more, better |
What is a non-directional (two-tailed) hypothesis? | When the person doesn't know what way the direction the results will go but there will be a difference. Key word: difference |
What is the independent variable? | The variable that is being manipulated in the study by the researcher. It is the thing that will change in the experiment |
What is the dependent variable? | Its the result of the change, It is the thing that is being measured. |
What is the operationalising variable? | When we operationalise a variable we are stating how that variable will actually be measured. |
Why is it necessary to operationalise a variable? | It allows for the experiment to be replicated |
What is a extraneous variable? | These are any variables, other than the IV, that may potentially affect the DV which can mix up the findings and affect the validity of the results. |
What is a situational factor? | This is anything about the environment which may affect their performance. EG. the time of day |
What is participants variables? | There are things that are specific to the participant that might affect the study. EG: age, gender, personality, intelligence |
What is demand characteristics? | When the participants form an idea of what the study is going to be about and they present the kind of response that they think the researcher wants, to please them but it ruins the results |
What is lack of standardisation in a procedure? | If different groups experience different things by different instructions this can lead to invalid results and the IV is not the only thing affect the DV. |
What is investigator bias? | The researchers expectations can influence how they design the study and behave towards the participants and their expectations may influence how they analyse the results. |
What is a piolet study? | Is a small-scale study that is done before the actual research is carried out. To establish weather the design works and the participants would understand the instructions and it saves time and money. |
What does control do in studies? | Makes sure that everything is the same for all participants eg. time of day, product etc. |
What is a experimental design ? | The way you organise your participants into groups |
What is independent design? | This is where there are different participants in each group |
Strength of independent design? | No order effects, no one will get better through practice or bored or tired (fatigue) |
Weaknesses of independent design? | Differences between the people in each group may affect the results
Number of participants: you are going to need double the participants, this can be more expensive. |
What is repeated measure design? | Where all the participants take part in every condition, ,this can be used to compare results from both conditions |
Strengths of repeated measure design? | The groups are made up of the same people so it won't affect the results.
Fewer participants, cheaper and less time consuming |
Weakness of repeated measure design? | Order effects: The task can become practiced but you can overcome this by counterbalancing |
What is counter balancing? | Mix up the order of tasks to overcome fatigue and boredom. |
What is matched pair desgin? | Similar to independent design seeing as they are in different conditions but each ppt is matched with someone in another group with an important variable that can affect the experiment eg. age, IQ (identical twins are often used) |
What are the strengths of matched pair design ? | No order effects: different people in each condition
Ppt's variables: important differences are minimised through matching |
What is a weakness in matched pair design? | Number of participants: need twice as many and time consuming to match pairs |
What is a labatory experiment? | Controlled and scientific, controls all relevant variables expect of the IV. Usually takes place in a specifically designed environment so it is easier to control. Ppts usually know that they are in a experiment but maybe not the true aim |
Strengths of lab experiment? | Control: high levels of control
It can be easily replicated |
Weaknesses of a lab experiment? | Artificial environment: low ecological validity
Demand characteristics: ppt's may respond to what they think the experiment is about
Ethics: ppt's usually deceived about the true aim |
What is a field experiment? | Behavior is measured in a naturalistic environment, ppt's are usually unaware they are in an experiment, deliberate manipulation of the IV |
Strengths of a field experiment? | Ecological validity: done in a real life setting, can be applied, less artificial than a lab experiment
Demand characteristics: ppt's don't know the true aim, can manipulate their behavior |
Weaknesses of a field experiment? | Less control: more extraneous variables are likely in a natural environment
Ethics: Often not debriefed, invasion of privacy |
What is a natural experiment? | The experimenter uses an IV that already exists, thats why its called natural because they didn't change the IV, they only record the effect that it has on the DV |
Strengths of a natural experiment? | Provides opportunities for research that wouldn't have been done otherwise
Validity: high validity because they study real life issues as they happen |
Weaknesses of a natural experiment? | Rare: these opportunities dont happen so often and difficult to generalise
Randomisation: Ppt's may not be randomly allocated, hard to tell if its only the IV thats affecting the DV |
What is a quasi experiment? | Naturally occuring IV but it already exisits, but it is the difference between people |
Strength of quasi experiment? | If it takes place in a lab, it has high levels of control |
Weakness of quasi experiment? | Low levels of control due to it taking place in a naturalistic environment, no cotnrol over extrenous variables. Not sure if only the IV is affecting the DV. |
What is random sampling? | Each member of a target audience is randomly selected. |
Strength of random sampling? | Equal chance to be selected and sample will mostly likely be representative |
Weaknesses of random sampling? | Does not guarantee a representative sample: small subgroups may not be selected and the person selected by refuse to take part |
What is opportunity sampling? | When the researcher picks whoever is available and willing to do the study, could be done by asking people on the street |
Strength of opportunity sampling? | Quick and practical |
Weaknesses of opportunity sampling? | Biased sample and unlikely to representative, members from the same target group. |
What is volunteer sampling? | People volunteer to study by responding to an advert |
Strength of volunteer sampling? | Least effort and most ethical because people choose to take part |
Weaknesses of volunteer sampling? | Sample is most likely to be biased, same personality traits, unlikely to be representative |
What is stratified sampling? | When there are subgroups in the target population and people are randomly selected from it. Ensure that it is proportionally representative |
Strength of stratified sampling? | More representative |
Weaknesses of stratified sampling? | The most time consuming and still might not guarantee and representative sample. |
What is naturalistic observation? | Observations in an environment that would be there normally eg, a town center, bus, park etc. |
Strength of naturalistic observation? | High ecological validity |
Weaknesses of naturalistic observation? | No control over extraneous variables |
What is controlled observation? | Some aspects of the environment is pre-set and controlled by the researcher |
Strength of controlled observation? | Can manipulate variables to observe |
Weaknesses of controlled observation? | reduced ecological validity and problems with investigator effects and observer bias. |