Research Methods in Psychology How do we study Psychology?

Goals of Psychological Research Define and Describe: What happened? Explain: Why did that happen? Predict: Under what conditions is that likely to happen again? Control: How can I we apply our principle to make this happen again? To make sure it never happens again?

IV’s and DV’s Independent variable (IV) : Variable the experimenter manipulates (i.e. changes) – assumed to have a direct effect on the dependent variable. Dependent variable (DV) : Variable the experimenter measures, after making changes to the IV that are assumed to affect the DV.

What is the independent variable? A researcher wants to determine if the color of an office has any effect on worker productivity. In an experiment, one group performs a task in a yellow room while another performs the same task in a blue room. In this example, the colour of the office is the independent variable.

What is the independent variable? Researchers want to learn whether listening to fast-paced music helps runners perform better during a marathon. In an experiment, one group of runners listens to fast-paced music while another group listens to slow-paced music. In this example, the type of music the runners listen to is the independent variable.

What is the independent variable? A business wants to determine if giving employees more control over how to do their work leads to increased job satisfaction. In an experiment, one group of workers is given a great deal of input in how they perform their work, while the other group is not. The amount of input the workers have over their work is the independent variable in this example.

What is the independent variable? Educators are interested in whether participating in after-school math tutoring can increase scores on standardized math exams. In an experiment, one group of students attends an after-school tutoring session twice a week while another group of students does not receive this additional assistance. In this case, participation in an after-school math tutoring is the independent variable.

What is the independent variable? Researchers want to determine if a new type of treatment will lead to a reduction in anxiety for patients suffering from social phobia. In an experiment, some volunteers receive the new treatment, another group receives a different treatment, and a third group receives no treatment. The independent variable in this example is the type of therapy.

What is the dependent variable? Researchers want to discover if listening to classical music helps students earn better grades on a mathematics exam. In this example, the scores on the mathematics exams are the dependent variable.

What is the dependent variable? Researchers are interested in seeing how long it takes people to respond to different sounds. In this example, the length of time it takes participants to respond to a sound is the dependent variable.

What is the dependent variable? Researchers want to know whether first-born children learn to speak at a younger age than second-born children. In this example, the dependent variable is the age at which the child learns to speak.

What is the dependent variable? Researchers are interested in looking at how alcohol use influences reaction times while driving. The amount of alcohol a participant injects is the independent variable, while their performance on a driving test is the dependent variable.

What is the dependent or Independant variable? Look at the question sheet: Can Science Answer This Question? Decide what would be the independent and dependant variables

Experiments Laboratory Experiments: These take place in either a lab or in a controlled environment setting, which is unnatural for the participants. They attempt to control all variables except the IV. By changing one variable (the IV) while measuring another (the DV) while we control all others, as far as possible, then the experimental method allows us to draw conclusions with far more certainty than any non-experimental method. If the IV is the only thing that is changed then a cause and effect relationship can be found between the IV ad the DV.

Experiments Field Experiments : Sometimes it is possible to carry out experiments in a more natural setting, i.e. in ‘the field ’. As with the laboratory experiment, the independent variable is still deliberately manipulated by the researcher. However it is not possible to have such tight control over variables in the field, but it does have the advantage of being far less artificial than the laboratory.

Experiments Natural (quasi) Experiments : Natural experiments may take place in the lab or field. Like other experiments they have an IV but in this type of experiment the experimenter does not directly manipulate the IV. Some IVs are not open to manipulation as some conditions are pre-decided by fixed characteristics. E.g. comparing men and women’s driving skills, they cannot be randomly allocated to be male or female. The IV is naturally occurring. Other examples of pre-existing variables might be age, IQ, position in the family and social background.

Experiments Your turn: Think of at least one strength and one weakness of a lab experiment, a field experiment and a natural (quasi) experiment. You have 10 mins max to complete this. Yes, write your answers down. Yes, you may discuss with a partner.

Experiments Laboratory Experiments: Strengths Laboratory experiments have high levels of standardisation and so can be replicated to test for reliability. As Laboratory experiments have high levels of control, researchers can be more confident it is the IV directly affecting the DV.

Experiments Laboratory Experiments: Weaknesses As laboratory experiments take place in an artificial setting, it is said that they can lack ecological validity. Many laboratory experiments make participants take part in tasks that are nothing like real life ones, so the tasks lack mundane realism. Participants usually know they are taking part in an experiment and they may respond to demand characteristics as something about the set-up indicates the aim of the experiment.

Experiments Field Experiments: Strengths As field experiments take place in a realistic setting, it is said that they have good ecological validity. As participants will not know they are taking part in a study, there will be little or no demand characteristics so behaviour is more likely to be natural and valid.

Experiments Field Experiments: Weaknesses Situational variables can be difficult to control, so sometimes it is difficult to know whether it is the IV affecting the DV. It could be an uncontrolled variable causing the DV to change. As participants will not know they are taking part in a study, there are issues with breaking ethical guidelines. These include the issues of informed consent and deception.

Experiments Natural (quasi) Experiments: Strengths As the experiment is located in a natural setting exploiting a naturally occurring IV, the study should be high in ecological validity. As participants are usually unaware that a study is taking place, their behaviour is more likely to be natural and a valid representation of each person’s behavioural repertoire

Experiments Laboratory experiments: Validity These experiments have high internal validity because controls mean the researcher can be confident it is the IV directly affecting the DV. They have low external validity as it may be difficult to apply the findings to a real life situation. Reliability These have high levels of reliability because controls and standardised procedures allow for full replication. Ethics It is usually easy to gain informed consent. Deception can be dealt with through a full debrief. Participants know they are in a study so can withdraw at any time. Internal validity refers to whether it is the IV directly affecting the DV External validity refers to the extent to which the findings of the study can be applied to real life settings and to other people outside the sample.

Experiments Field experiments: Validity These experiments have lower internal validity as the researcher can control some variables but not all of them. There is stronger external validity than in laboratory experiments due to the “field” setting of the study. Reliability These have medium levels of reliability as some elements of the study are controlled with some standardised procedures but full replication may be difficult. Ethics Researches can gain informed consent from participants, but it is not always possible. Participants may not know they are part of a study which can make debriefing difficult and sometimes impossible. (Also if participants do not know they are in a study their right to withdraw is invalidated)

Experiments Natural (quasi) experiments: Validity These experiments have low internal validity as there is no control over any extraneous variables. Natural experiments have high external validity as they take place in participants’ natural environment. Reliability These have low levels of reliability as there is hardly any controls or standardisation and this makes replication very difficult. Ethics There are several issues. Informed consent can be very difficult to obtain, depending on the study. People may not know they are part of a study which can make debriefing difficult and sometimes impossible. (Also if participants do not know they are in a study their right to withdraw is invalidated)

The Marshmallow Test

Dictionary Your task: Cut out the key words and match them to the definitions.