Psychology a level - PART 2 research methods

content

a strength and limitation of random sampling

no researcher bias, unrepresentative

what is randomisation

the use of chance to reduce the effects of bias from investigator effects

how to eliminate order effects from repeated measures

counterbalancing

describe a single blind experiment

the researchers are aware of which subjects are receiving the independent variable, but the participants of the study are not

what is standardisation

keeping everything the same for all participants so that the investigation is fair

what is stratified sampling

a sampling method in which researchers first divide a population into smaller subgroups, or strata, based on shared characteristics of the members and then randomly select among each stratum to form the final sample

what is systematic sampling

a sampling method where every nth individual is selected from a list or sequence to form a sample, ensuring even and regular intervals between chosen subjects

what does it mean if a conclusion has high temporal validity

it can be generalised over time

describe time sampling and give a specific example

the researcher records all behaviours for a set time frame, at a set point, e.g. they record each participant behaviour for 20 seconds every 15 minutes over a 2 hour observation

what is validity

the extent to which research accurately measures what it’s intended to measure

describe volunteer sampling and give a specific example

people sign up for the study on their own accord e.g. by replying to an advert in a newspaper

why might volunteer sampling be biased/unrepresentative

everyone who signs up has a participant variable in common

what is interval data

anything measured in public, standardized units such as height or speed

what is ordinal data

any data on a rating scale, a position, or results of a non-standardized test

what is nominal data

measures how many people fall into each category. you can’t identify an individual score

give 3 measures of central tendency

mean, median, mode

give 2 measures of dispersion

range, standard deviation

when should the mean be used as a measure of central tendency

when there are no anomalies

when should the median be used as a measure of central tendency

when the mean cannot be used due to anomalies

when should the mode be used as a measure of central tendency

when there is a clear modal value. always use when dealing with nominal data

3 things to include when drawing a graph

a title with the IV and DV in it, labelled axis, IV on X-axis and DV on Y-axis

when is a bar chart used

when the data is discreet, in separate categories

do the columns touch in a bar chart

no

when is a histogram used

when the data is on a continuous scale e.g. when the numbers are consecutive on the x-axis

do the columns on a histogram touch

yes

when would a scattergram be used

when the relationship between two co-variables is being assessed in a correlation study

when would a line graph be used

when change over time is being measured

define normal distribution

When data is plotted on a graph, a bell-shaped curve is given, and the mean, median, and mode are all the same

give 2 examples of features believed to be normally distributed within the UK

IQ, height

which average is the biggest in a negatively skewed distribution

mode

which average is the biggest in a positively skewed distribution

mean

which direction is a negatively skewed distribution skewed towards

left

what is content analysis

quantifying qualitative data through coding and analysing the results

what is qualitative data

detailed data in the form of words

what is coding

breaking down qualitative data using operationalised categories and tallying the number of times a category occurs

what is thematic analysis

looking for broader ‘themes’ in qualitative data, which may be decided after a content analysis

how is a sign test carried out

work out the differences between the two conditions. then make note of whether these are positive or negative. make note of the number of the less frequently occurring sign (this is calculated value). N is the number of participants, excluding those who’s sign was = then use table, as 0.05 significance, to decide on the critical value

what is a type 1 error

an optimistic error, where the level of significance is too lenient

what is a type 2 error

a pessimistic error, where the level of significance is too strict

what does a stat test of a correlation need to achieve

a test of the significance of a relationship

what does a stat test comparing 2 conditions need to achieve

a test of significance in difference

which stat test would you use for a correlation that created interval data

pearson moment

which stat test would you use for a matched pairs design with ordinal data

wilcoxon sign

which stat test would you use for an independent measures design with nominal data

chi squared

acrostic for choosing a sign test

never

order

indian

rice

soup

while

rating

men

sides

when

rating

iguanas

can’t

mean

u

can’t

even

costs

so

poorly

3 ways to improve reliability

train observers, standardise procedures, operationalize

3 ways to improve validity

controlled environment, standardise procedures, single or double-blind design

what is the aim of the ‘nudge unit’

to change the behaviour of the population in a way that helps the government and economy, one small bit at a time

two ways in which psychology helps the economy

treatment for mental disorders like depression allows people to spend less time off work

research into role of the father reassures high-earning mothers that they can continue to work so families may maximise their income

what are the different sections of a report

abstract

overview of the approach

structure of the data

structure of the model

results

discussion

references

what is the structure of a book reference

Surname and initial of author, (year published) title of book, place of publishing, publisher, page number

what is the structure of a journal article reference

Surname and initial of article writer (year published) ‘Title of study or theory’, surname and initial of book author, (year published) title of book, place of publishing, publisher, page number

what is the structure of a website reference

source, (year) title, weblink, date accessed

what is peer-review

the process by which research reports are sent before publishing to other, hopefully unbiased, psychologists who are specialists in the field being investigated. These psychologists will hopefully point out any unjustified conclusions or flaws in the method

2 limitations of peer-review

long process

only significant findings are published which may lead to bias within the field (file-drawer problem)

2 strengths of peer review

ensures ethical research

prevents invalid findings from being published

define science

a branch of knowledge conducted on objective principles involving the systematised observation of and experiment with phenomena

give 8 features of science

objectivity, empirical method, replicability, falsifiability, theory construction, hypothesis testing, paradigms, paradigm shifts

give an acronym for the levels of data

ION

difference between natural and quasi experiment, giving an example for each

natural = IV not manipulated by researcher but manipulated by past experiences e.g. maternal deprivation

quasi = IV not manipulated by anyone e.g. gender