4.2.3.1 Scientific Processes Flashcards
What is an empirical method?
When information is gained from direct observation, so it can be certain that claims of knowledge are true
What are research methods?
Techniques used to gather data about the mind and behaviour
What is the experimental method of research?
A research method that is used to identify the effect on one variable on other variables, known as cause and effect. They must follow scientific methods and be a true experiment.
What is falsifiability?
The principle that a theory cannot be considered scientific unless it allows the possibility of being proved untrue
What is a true experiment?
A true experiment has a control condition and an experimental co Dionysus, and participants must be randomly assigned to each one, so the researcher can make fair comparisons.
Give examples of research methods
-experiments
-observations
-survey
-interview
-correlations
-case studies
What is the experimental condition?
The condition in which there has been researcher manipulation to see if a change in behaviour has occurred.
What is the control condition?
Provides a baseline measure of behaviour without any experimental treatment.
What is the independent variable?
The variable that is manipulated by the researcher, or changes naturally.
What are control variables?
When all other variables that might potentially effect the DV are kept constant, so the researcher can be confident that any change in the DV was due to only the IV.
-this achieves internal validity
What are extraneous variables?
Variables that may effect the dependant variable if not controlled.
What is the dependant variable?
The variable that is measured by the researcher. Any changes to h the DV should be due to changes in the IV only.
What is operationalisation?
Clearly defining variables, and making them specific, so that they can be measured.
-this allows psychologists to communicate their findings to others, and others to replicate their experiments
What is an aim?
A general statement of what the researcher intends to investigate and the purpose of the study. Aims tend to be developed from theories.
What is an alternate/experimental hypothesis?
Predicts a significant difference or relationship between the two variables. It can be directional or non -directional.
What is a hypothesis?
A precise and testable statement that states the relationship between the variables in the investigation. It predicts the outcome of the study.
What is a null hypothesis?
Predicts that there will be no significant difference or relationship between the two variables.
What is a directional hypothesis?
-also known as a one-tailed hypothesis
It states the direction of the difference or relationship, to identify the sort of relationship that may be seen.
When would a directional hypothesis be used?
When previous research indicates the probable direction of the results.
What is a non-directional hypothesis?
-also known as a two-tailed hypothesis
It does not state the direction of the difference or relationship.
When would a non-directional hypothesis be used?
When there has been no previous research to suggest what direction the research will go in, or previous research has been contradictory.
What are the 5 key steps in writing a hypothesis?
-identify the IV and the DV (what is being manipulated and what is being measured?)
-create a comparison of the experimental conditions to show how the IV is being manipulated
-operationalise the DV to state how it is being measured
-decide whether to write a directional or non-directional hypothesis
-put all of the information together in a testable written statement
Write a non-directional hypothesis to suggest whether age affects short-term memory
There will be a significant difference in the short term memory, measured by a score out of 10 on a word memory test, in participants who are older in years, compared to those who are younger in years.
Write a directional hypothesis for the effect of higher temperatures on the growth of tomato plants
Tomato plants that grow in higher temperatures of 25c will grow a greater number of millimetres per day, than tomato plants that grow in lower temperatures of 15c.
Write a null hypothesis for the effect of lack of sleep on reaction time?
There will be no significant difference in the reaction time, measured in milliseconds by the ruler drop test, of participants who have slept for a greater number of hours the previous night, compared to those who have slept for a fewer number of hours the previous night.
What are experimental designs?
Refers to the different ways in which the testing of participants can be organised, in relation to experimental conditions.
Describe how independent groups work
-different participants are tested in each condition of the experiment
-one group is assigned to the control condition, and one to the experimental condition
-they are compared to identify differences in the dependant variable
-random allocation decides which participants go to which condition
Strengths of independent groups?
-simplest design to operate
-eliminates order effects
-reduces demand characteristics
-same test can be used for both groups
What are order effects?
Include practise, boredom and fatigue, and are caused by people taking part in more than one trial.
What are demand characteristics?
Occur when participants have guessed the aim of the experiment
(Please you and screw you effect)
Weaknesses of independent groups?
-weak control of participant variables and individual differences, so random allocation needs to be used
-it is uneconomical with participants as it requires more.
What are individual differences?
Variables in the participants in each condition, that may contribute to the change in the DV, therefore becoming extraneous variables.
What are the benefits of random allocation?
-removes researcher bias
-removes participant bias
-increases validity
Strengths of repeated measures?
-eliminates the effects of individual differences as same participants take part in both conditions
-requires fewer participants
Weaknesses of repeated measures?
-creates order effects
-requires counterbalancing so is more complicated
-risk of demand characteristics (please u and screw u)
Describe how a repeated measures experiment works?
-participants take part in all of the conditions
-their performance in each condition is compared
-the order at which they carry out the conditions should be randomised
What is counterbalancing?
-half of the participants start in one condition, and the rest start in the other.
-this controls the impact of order effects, as it allows them to be distributed evenly across both conditions.
Describe how a matched pairs experiment works
-each participant is matched with another participant on characteristics which are considered relevant to the experiment eg. Age or intelligence
-one participant from each pair is allocated at random to each condition
-this process assumes they are similar enough to be treated s one person
Weaknesses of matched pairs?
-time consuming, and so uneconomical
-complete matching is not possible
-if one participant drops out, the nature of the study means that two participants are lost
What is an extraneous variable?
A variable that is not the independent variable, but may affect the dependant variable if not controlled. These variables do not systematically vary with the IV, so we cannot be sure if it has affected the DV.
How do psychologists aim to control extraneous variables?
It is very important that these variables are controlled, to be sure that it is the IV that affects the DV. Psychologists aim to identify them at the start of the study so that they can control them.
What is a confounding variable?
A variable which has affected the DV, and therefore the outcome of the study. These systematically vary with the IV, so we can be sure that it has affected the DV. They aren’t often recognised until critical inspection by others later on.
What are participant variables?
Refer to the different characteristics of participants which may affect the outcome of an experiment eg. Age or intelligence
What are situational variables?
Refer to factors in the environment which may affect the outcome of an experiment eg. Time of day or temperature. These become even more problematic when only one of the groups is affected.
What are demand characteristics?
Occur when participants try to make sense of the research situation they find themselves in, and act accordingly.
-trying to guess the purpose of the research and acting in a way they feel is helpful
-trying to guess the purpose of the research and acting in a way they feel is unhelpful
-evaluation apprehension- nerves due to the research setting
-displaying social desirability bias to be seen as favourable
Why are demand characteristics problematic?
They do not represent participants normal behaviours and actions outside of the research situation, which means the data becomes invalid. Therefore, well-designed research aims to minimise their effect.
How do psychologists minimise the effects of demand characteristics?
By using the single blind procedure
-participants are not informed about the condition they are placed in and aren’t aware often the aim of the research, as not to seek clues
-however this raises ethical issues of deception and informed consent
What are investigator effects?
The effects of the investigator’s conscious or unconscious behaviour on the research outcome.
-It is difficult for the investigator to remain impartial, as they have expectations and personal characteristics that may affect the behaviour of participants eg. Unconsciously designing the study to produce the desired outcome, or misinterpreting findings to support the original hypothesis.
How do psychologists reduce investigator effects?
-Double blind procedure: neither the investigator nor the participants know the aim or hypothesis of the study
-Computerised testing: participants interact with a computer rather than a human investigator. It also means data can be stored on the computer, making it harder to mis-record the information from participants.
What is randomisation?
The use of chance methods to control for the effects of researcher or investigator bias when designing materials, and deciding the order of experimental conditions. It ensures the investigator has no control over certain key features.
What is standardisation?
Using exactly the same formalised procedures for all participants in a research study. This includes environment, instructions and experience.
What does the type of experiment depend on?
How the IV changes, and under what circumstances it does so.