1.21 Year 2 Research Methods - Parametric Tests

Question 1

Parametric Tests

Answer 1

Stats tests can sometimes be more powerful than others; these are known as parametric tests. These can detect significant that some others cannot, three of these looked at:

• Unrelated T-Test
• Related T-Test
• Pearson’s R

Question 2

There are three criteria that must be met to use the three parametric tests, what are they?

Answer 2

• Interval data
• Normal distribution
• Homogeneity of variance

Question 3

Interval data

Answer 3

Actual scores that measure based on fixed units that make a %

Question 4

Normal distribution

Answer 4

Data should be drawn from a population which would expect to show normal distribution for the variable being measured e.g. random sample from general population when measuring IQ

Question 5

Homogeneity of variance

Answer 5

set of scores in each condition should have similar dispersion. Can be checked using standard deviation e.g. if SD is 0.4 and 1.8 they are very different so parametric test not used, if SD is 0.4 and 0.5 however it would be as they are very similar

Question 6

When psychologists write up their experiment they produce a scientific report with 6 sections:

Answer 6

• Abstract: Short summary 150-200 words in length outlining all major elements like aim, hypotheses, method, results and conclusions. When researching a topic, psychologists read lots of abstracts to identify which investigations worthy of further investigation
• Introduction: Review of general area of investigation detailing relevant theories, concepts and studies related to current study.
• Method: Split into several sub-sections:
  o Design: The design is clearly stated e.g. independent groups naturalistic etc. with justification for this choice given.
  o Sample: Info related to people involved in the study e.g. numbers, demographics, sampling type and target
  o Apparatus: Details of any assessment used and other relevant materials
  o Procedure: A list of everything that happened in the experiment from beginning to end including a verbal record of everything that was said to participants in the briefing, instructions and debrief
  o Ethics: An explanation how they were addressed
• Results: A summary of the key findings of the study likely to include descriptive statistics such as table graphs and charts. Measures of central tendency and dispersion. Inferential statistics also used and should include a reference to the choice of stats test and the calculated and critical values, level of significance and final outcome. Raw data collected and any calculations appear on the appendix rather than main report. In cases of qualitative methods being used it is likely to involve analysis of themes and categories.
• Discussion: Summary of the results in verbal rather than statistical form. Should be discussed in the context of the evidence presented in the introduction and other possibly relevant information. Researcher needs to mindful of the limitations of present investigation and discuss those as part of this section. May reference aspects of the method or sample and some suggestion of limitations and how they could be addressed or how they were addressed.
• References: A summary of any sources that they gained information from to avoid being accused of plagiarising.

Question 7

Evaluation of peer re

Answer 7

• Anonymity: Rival researchers may use this as an opportunity to unfairly criticise rival research that impacts their own. This is especially likely because psychologists need to compete for funding
• Publication Bias: It is natural for editors to want to attract as many people as possible to their findings which can lead to a manipulation of results which gives an inaccurate image when releasing journals creating a false impression of what the current state of psychology is, due to this selectivity
• Burying ground breaking research: Some research may contradict highly established science and past theories which may lead to them being buried because there is a lack of willingness to accept such radical and different ideas so quickly.

Question 8

Implications of research on the economy

Answer 8

• Research on mental illness: Absence from work costs the economy an estimated £5 Billion a year with 33% of this being linked to depression, by treating depression and reducing its impact the economy is better off because less money is lost to sick pay.
• Role of the father: Importance into the role of the father has allowed for the offering of paternity leave as well as maternity leave which allows for the mother to return to work and reduces the amount of time each individual parent is off work because of this split.
• Eyewitness on memory: By improving the way we ask eyewitnesses things we can gain better recall into the sequence of events at a crime. This leads to more info being gathered which allows us to process criminals more efficiently which will reduce the cost of policing.

Question 9

What are the 5 features of science

Answer 9

• Paradigms and Paradigm shifts
• Theory construction and hypotheses testing
• Falsifiability
• Replicability
• Objectivity and Empirical methods

Question 10

Paradigm

Answer 10

Consists of basic assumptions and ways of thinking and method of studying commonly used members of a group

Question 11

Paradigm shift

Answer 11

A change from one way of thinking to another, also referred to as scientific revolution

Question 12

Theory

Answer 12

Provides a model for understanding human thoughts, emotions and behaviours

Question 13

Hypothesis

Answer 13

Statement about behaviour between two variables and what it is thought will happen

Question 14

Falsifiability

Answer 14

The principle that a theory cannot be considered scientific unless it admits the possibility of being proven untrue e.g. Freud’s theory on phobias and displacement

Question 15

Replicability

Answer 15

The extent to which scientific procedures and findings can be repeated by other researchers

Question 16

Objectivity

Answer 16

When all sources of personal bias are minimalised so as to not distort or influence research process

Question 17

Empirical methods

Answer 17

Scientific approaches based on the gathering of evidence through direct observation and experience.