Research Methods Flashcards
(329 cards)
1
Q
What are the 4 types of experiment?
A
- laboratory
- field
- quasi
- natural
2
Q
What is a laboratory experiment?
A
- researcher has a high level of control over all variables
- uses standardised procedures to ensure the experience of each participant is the same
- manipulates the IV to measure the DV
3
Q
What are the strengths of a lab experiment?
A
- can establish cause and effect
- have a high internal validity
- replicable due to standardised procedures
4
Q
What are weaknesses of a lab experiment?
A
- lacks ecological validity
- lacks mundane realism
- participants may be subject to demand characteristics
5
Q
What is a field experiment?
A
- conduct experiment in naturalistic settings
- IV is manipulated and DV is measured
6
Q
What are the strengths of a field experiment?
A
- higher ecological validity
- higher mundane realism
- less likely to be subject to demand characteristics
7
Q
What are the weaknesses of a field experiment?
A
- lack of control over extraneous variables
- cannot randomly allocate participants so there is the impact of participant variables
8
Q
What is a natural experiment?
A
The IV is naturally occurring
9
Q
What are strengths of a natural experiment?
A
- allows research in areas that otherwise may have been unethical
- high external validity
10
Q
What are weaknesses of a natural experiment?
A
- extraneous variables cannot be controlled
- studies are rare so lack replicability
11
Q
What is a quasi experiment?
A
Where participants cannot be randomly assigned as the IV is an innate characteristic e.g. gender or age
12
Q
What are the strengths of a quasi experiment?
A
- only way to study pre existing factors
13
Q
What are weaknesses of a quasi experiment?
A
- impact of confounding variables
- demand characteristics
14
Q
What is an observation?
A
A non experimental technique where the researcher watched and records behaviour
15
Q
What are the types of observation?
A
- controlled
- naturalistic
- overt
- covert
- participant
- non participant
16
Q
What is a controlled observation?
A
Environmental factors are controlled to give participants the same experience often in a lab setting
17
Q
What are the strengths of a controlled observation?
A
- reduces likelihood of extraneous variables impacting the study
- reliable results due to standardised procedures
18
Q
What are the weaknesses of controlled observations?
A
- artificiality of the setting may result in unnatural behaviour
19
Q
What is a naturalistic observation?
A
Observation that takes place in a real life environment
20
Q
What are the strengths of naturalistic observations?
A
- high realism so participants are more likely to show natural behaviour
- high external validity
21
Q
What are the weaknesss of naturalistic observations?
A
- uncontrolled extraneous variables meaning there is a lower internal validity as
22
Q
What is an overt observation?
A
When participants know they are being studied
23
Q
What are strengths of overt observations?
A
- more ethical as have gained fully informed consent
24
Q
What are weaknesses of overt observations?
A
- participants are more subject to demand characteristics
- social desirability bias
25
What is a covert observation?
When participants aren’t aware they are being studied
26
What are strengths of covert observations?
- more likely to show naturalistic behaviour reducing demand characteristics
27
What are weaknesses of covert observations?
- more unethical as cannot gain fully informed consent
28
What are participant observations?
Researcher joins the group and takes part in the activity
29
What are strengths of participant observations?
- build a rapport with participants so they are more likely to display natural behaviour
30
What are the weaknesses of participant observations?
- lose objectivity
- researcher bias
31
What is a non participant observation?
Researcher is separate from the group and doesn’t take part
32
What are the strengths of non participant observations?
- remains objective
33
What are weaknesses of non participant observations?
- lack of rapport so researcher can miss out on important insight
34
What are unstructured observations?
Has no defined behavioural categories
35
What are strengths of unstructured observations?
- can gain more detailed insight
- behaviour is more naturalistic
36
What are the weaknesses of unstructured observations?
- susceptible to observer bias
- lack of control
37
What are structured observations?
Systematically observing and recording clearly defined behaviours
38
What are strengths of structured observations?
- standardised so more replicable
39
What are weaknesses of structured observations?
- may miss important insight
40
What is meant by observational design?
The choice of what behaviours to record and how they are measured
41
What is meant by operationalised behavioural categories?
Behaviours must be clearly defined and measurable
42
What are the 2 types of sampling for observations?
- time sampling
- event sampling
43
What is time sampling?
Researcher records all relevant behaviour at set points e.g. for 1 minute every 5 minutes
44
What are strengths of time sampling?
- more flexibility to record unexpected behaviour
45
What are weaknesses of time sampling?
- can miss behaviours that happen outside of the recording period
46
What is event sampling?
Researcher records every time an identified behaviour occurs from the list of operationalised behavioural categories
47
What are strengths of event sampling?
- no behaviours are missed if they are on the list
48
What are weaknesses of event sampling?
- can miss behaviours that weren’t on the list
49
What does assessing reliability of observations mean?
Seeing if results are consistent with other researchers observations
50
How can we assess reliability of observations?
- inter observer reliability
- multiple trained observers conduct the observation separately using same operationalised behavioural categories
- compare findings using a correlation stats test
51
What is meant by self report techniques?
Participant reveals personal information about themselves in response to questions
52
What are the 2 types of self report techniques?
- interviews
- questionnaires
53
What are interviews?
Participants give information in response to direct questioning from a researcher
54
What are questionnaires?
Participants give information in response to set questions given to them
55
What are the 2 types of questions that can be asked?
- open
- closed
56
What are open questions?
Questions that are phrased in ways that allow participants to answer how they choose
57
What type of data do open questions produce?
Qualitative
58
What are strengths of open questions?
- provide more valid, detailed results
59
What are weaknesses of open questions?
- data analysis is hard so patterns are hard to spot
60
What are closed questions?
Questions are phrased in ways that limit the responses to certain options
61
What type of data do closed questions produce?
Quantitative
62
What are strengths of closed questions?
- quantitative data is easy to analyse
63
What are weaknesses of closed questions?
- less detailed responses so less valid
64
What factors need to be considered in questionnaire construction?
- avoiding complex terminology
- reword questions so questions are clear
- avoid leading questions
- should pilot questions prior to
- use filler questions
65
What are the strengths of questionnaires?
- don’t need a trained interviewer
- easily distributed and collected
- when using closed questions comparisons can be made
66
What are the weaknesses of questionnaires?
- questions cannot be rephrased if they don’t understand it
- may not be taken seriously
67
What are structured interviews?
Interviewer reads out a prepared list of questions
68
What are strengths of structured interviews?
- interviewer doesn’t have to be highly trained
- interview responses are easy to compare
69
What are weaknesses of structured interviews?
- responses cannot be followed up to get more detail
70
What are unstructured interviews?
There isn’t a set list of questions so can have an open conversation about the topic
71
What are the strengths of unstructured interviews?
- can build a rapport so the participant is more likely to disclose information
- interesting responses can be followed up
72
What are the weaknesses of unstructured interviews?
- interviewer needs to be highly trained
- making comparisons is hard
73
What is a semi structured interview?
A combination of prepared questions with the ability to ask additional ones
74
What are strengths of semi structured interviews?
- responses can be compared
- interviewer can ask follow up questions
- can build a rapport
75
What are weaknesses of semi structured interviews?
- needs a highly trained interviewer
76
What are strengths of interviews?
- can rephrase questions that are hard to understand
- can build a rapport with participant
77
What are weaknesses of interviews?
- requires an interviewer which increases cost
-susceptible to interviewer effects
78
What are strengths of self report techniques?
- same set of questions can be used each time so it is easy to design
- when closed questions are used data analysis can be used
79
What are weaknesses of self report techniques?
- suffers from bias
80
What are the types of bias that are present in self report?
- demand characteristics
- researcher bias
- investigator effects
- social desirability bias
81
What is measured in a correlational study?
The impact of one co-variable on another to find the relationship
82
What are co-variables?
The two factors being measured and compared
83
What is a scattergram?
A ralph used to plot the measurements of co-variables
84
What is a positive correlation?
As one co-variable increase the other increases
85
What is a negative correlation?
As one co-variable increases the other decreases
86
What is zero correlation?
The co-variables have no relationship
87
What does a correlation with a coefficient of -1 mean?
Perfect negative correlation
88
What dos a correlation with a coefficient of 0 mean?
No correlation
89
What does a correlation with a coefficient of +1 mean?
Perfect positive correlation
90
What are the strengths of correlations?
- can highlight causal relationships to be further investigated
- data is normally pre existing so few ethical issues in data collection
- correlation coefficient is useful in describing the relationship
91
What are the weaknesses of correlations?
- correlation doesn’t mean causation
92
What is a content analysis?
An indirect observational method that analyses human behaviour through studying artefacts e.g. adverts
93
What is the aim of a content analysis?
Turn qualitative data into quantitative data
94
How do you execute a content analysis?
- decide on a research question
- select the sample
- decide on coding units
- work through the sample and tally the number of times the coding units appear
- analyse the quantitative data to look for patterns
95
What are coding units?
The categories that are being recorded that must be operationalised
96
How do you test a content analysis for reliability?
- test retest
- inter rater reliability
- test of correlation between sets of data collected
97
What are strengths of a content analysis?
- artefacts aren’t usually created for the research so have a high external validity
- artefacts are easy to gather
- easy to replicate a content analysis
98
What are the weaknesses of content analysis?
- researcher bias as they may interpret artefacts to match their hypothesis
- artefacts weren’t created under controlled conditions
99
What is a thematic analysis?
Researchers attempting to identify deeper meaning of data allowing themes to emerge
100
How do you execute a thematic analysis?
- collect text/transcribe
- read text to identify emerging themes
- reread to further refine themes
101
What are strengths of thematic analysis?
- as theories come after the themes it isn’t impacted by researcher bias
- high external validty
- easy to collect sample
- easy to replicate a content
102
What are weaknesses of thematic analysis?
- subjective interpretation
- data isn’t created in controlled conditions
103
What is an aim?
Clear general statement about what tine researcher is intending to study
104
What is a hypothesis?
Precise testable statement predicting the outcome of the study
105
What does operationalisation mean?
Making variables clear and precise
106
What is the null hypothesis?
Predicts there will be no change in the dependent variable as a result of the independent variable
107
What is the alternative/experimental hypothesis?
States the change in the dependent variable as a result of the independent variable
108
What is a non-directional hypothesis?
States there will be a difference in the DV as a result of the IV but not the way it will change
109
What is a directional hypothesis?
Predicts the direction of the difference in the DV as a result of the IV
110
When should a directional hypothesis be used?
Only if there is previous research to suggest the direction
111
What is sampling?
The process of choosing the sample who will take part in the study
112
What is the target population?
Every member of the group the researcher intends to generalise the findings to
113
What are the types of sampling?
- random
- systematic
- opportunity
- volunteer
- stratified
114
What is random sampling?
Each member for the target population has an equal chance if being in the sample
115
What are the strengths of random sampling?
- avoids researcher bias
116
What are the weaknesses of random sampling?
- could lead to an unrepresentative sample
- difficult and time consuming
117
What is systematic sampling?
Choosing every nth person from a list
118
What are the strengths of systematic sampling?
- avoids researcher bias
- quick if there is an existing list
119
What are the weaknesses of systematic sampling?
- could result in an unrepresentative sample
- if target population is large getting a list can be hard
120
What is opportunity sampling?
Researcher approaches members of target population that are available and asks if they would like to take part in
121
What are strengths of opportunity sampling?
- fastest way to get a sample
122
What are weaknesses of opportunity sampling?
- researcher bias as may approach same kind of people
- likely to be unrepresentative
123
What is volunteer sampling?
Participants offer to take part in the research
124
What are strengths of volunteer sampling?
- adverts can reach lots of people
- easy to collect sample
125
What are weaknesses of volunteer sampling?
- likely to be unrepresentative
- volunteer bias
126
What is stratified sampling?
Selecting a sample with the same proportions as the target population
127
What are strengths of stratified sampling?
- representative
- avoids researcher bias as use random sampling too
128
What are weaknesses of stratified sampling?
- not all characteristics can be taken into account
- time consuming
129
What is a pilot study?
Small scale trial run of a study prior to the actual study
130
What is the aim of a pilot study?
- control unexpected extraneous variables
- clear up confusing tasks/questions
- reduce any demand characteristics
- find out whether it is time consuming
- ensure behavioural categories are fully operationalised
131
What are the 3 types of experimental design?
- independent groups
- repeated measures
- matched pairs
132
What is independent groups design?
- different participants complete different conditions
- participants are randomly allocated
- produces unrelated data
133
What are the strengths of independent groups?
- no order effects
- reduces demand characteristics
134
What are weaknesses of independent groups?
- participant variables
135
What is repeated measures design?
- same participant completes all conditions
- produces related data
136
What are the strengths of repeated measures?
- no participant variables
137
What are the weaknesses of repeated measures?
- order effects
- demand characteristics
138
What is the matched pairs design?
- participants are paired up and the members of each pair complete different conditions
- randomly allocated to conditions
- produces related data
139
What are strengths of matched pairs?
- reduced participant variables
- no order effects
140
What are weaknesses of matched pairs?
- takes longer to set up
- still some participant variables
141
What is the dependent variable?
The variable the researcher measures
142
What are extraneous variable?
Any variable that could effect the DV
143
What is the independent variable?
The variable the researcher manipulates/changes
144
What are demand characteristics?
Participants guess the aim of the study and behave accordingly
145
What are participant variables?
Individual differences between participants that do different conditions of the study
146
What are situational variables?
Environmental factors that are present in one condition but not others
147
What are order effects?
When individuals do all conditions of the study and behaviour alters due to practice, boredom or fatigue
148
What are confounding variables?
A variable other then the IV that changes between levels of IV
149
How do you control participant variables?
- random allocation of participants
- randomisation of materials
- matched pairs design
150
How do you control order effects?
- counterbalancing
151
What is counterbalancing?
When half the participants do condition A then B and the other half do condition B then A
152
How do you control situational factors?
- standardising the procedure so participants have them same experience
153
How do you control demand characteristics?
- single blind trials
- double blind trials
154
What are single blind trials?
Participant doesn’t know the aim of the study and
155
What are double blind trials?
Participant and person executing the study don’t know the aim of the study
156
What are investigator effects?
The investigators own personal characteristics that can impact the study
157
What is a case study?
When data is collected from individuals/small groups/events that is highly detailed
158
Who are case studies conducted on?
- psychologically unusual individuals
- unusual events
- organisational practices
- typical individuals within a demographic
159
What are the strengths of case studies?
- holistic approach to data collection giving valid insights
- often the only way to study unusual/extreme behaviour
- can be used to generate a hypothesis
160
What are weaknesses of case studies?
- interviews are often used which have methodological issues
- lack reliability as can’t be replicated
- can suffer from research bias
161
What is the role of the BPS?
Provide an ethical code of conduct
162
What are the ethical issues?
- lack of informed consent
- deception
- lack of right to withdraw
- lack of protection from harm
- lack of confidentiality
- lack of privacy
163
What is lack of fully informed consent?
Participants must be given comprehensive information about purpose of the study to make an informed decision on whether to participate
164
How do you solve a lack of fully informed consent?
Gaining presumptive consent and then fully informed consent after the study
165
What is deception?
When participants aren’t told true aims of study
166
How do you solve deception?
Gaining presumptive consent and fully debrief afterwards
167
What is the lack of right to withdraw?
Participants should be able to pull out of the study at any point
168
How is a lack of right to withdraw solved?
Ensuring participants know they can leave at any point
169
What is a lack of protection from harm?
When the study may cause physical or psychological harm
170
How do you solve a lack of protection from harm?
Avoid risks and stop the study if needed
171
What is a lack confidentiality?
Personal information isn’t kept protected and anonymous
172
How do you solve a lack of confidentiality?
Researchers shouldn’t record any names anywhere and should use false names
173
What is a lack of privacy?
Participants don’t know who knows what about them
174
How do you solve a lack of privacy?
Don’t study anyone without fully informed consent
175
What are the types of consent?
- prior general consent
- retroactive consent
- presumptive consent
176
What is prior general consent?
Participants agree to a long list of potential features that may occur
177
What is retroactive consent?
Asking for consent after the study
178
What is presumptive consent?
Researcher asks a similar group to the sample if they would consent and assume the sample would think the same
179
How do researchers weigh up the harms and benefits of their research?
Cost benefit analysis
180
What is a peer review?
When a researchers paper is assessed by experts in the same/similar field
181
How is a peer review conducted?
- submit the paper to a scientific journal and it is sent to peers
- peers consider quality of the paper and the research considering any extraneous variables and data analysis
- peers decide if the paper should be published
- if accepted the journal editor will publish is and if rejected changes will be made if possible
182
What are the strengths of peer review?
- knowing their work will be checked increases likelihood of researchers taking care when planning and executing the research
- media often reports research so helps to determine whether claims should be trusted
- research labs producing peer reviews research are more trusted
183
What are weaknesses of peer reviews?
- hard to find suitable peers
- peers may prevent research being published so they can do it first
- publication bias if negative findings aren’t published
184
What is meant by the economy?
Production and consumption of goods and services
185
What is psychology and the economy?
Psychological theories are applied to government/companies to improve the economy
186
What are 3 general impacts of psychology on the economy?
- psychologically healthy and educated populations are more productive
- psychological understanding of desire will increase sales
- more people that can work will increase taxes paid
187
What impact did maternal deprivation research have on the economy?
- midwives can use the knowledge as advice to parents
- improved hospital visit policies
- adoption agencies will prioritise quick placements
- all results in adults being more productive
188
What impact did social influence research have on the economy?
- can use it to influence people to pay more taxes
- provides more funding for other services
189
What impact does conditioning in social media have on the economy?
- virtual rewards e.g. likes and follows
- more people using social media platforms so more adverts can be displayed
190
What impact does neurotransmitter drug treatments have on the economy?
- cheap effective treatments
- reduce NHS costs
- improve worker productivity
191
What impact does memory in the justice system have on the economy?
- reduces cost of imprisoning people wrongly accused of
192
What is reliability?
When results are consistent when replicated
193
What is external reliability?
The extent to which the results are consistent when repeated
194
What is internal reliability?
The extent to which different parts of the research are consistent with itself e.g. 2 50 question quizzes found similar results
195
How do you assess internal reliability?
- split half method
196
What is the split half method?
- split the test into 2 half’s
- participants complete both parts
- test of correlation strength between results of the 2 parts
- strong correlation indicates high internal validity
197
How do you assess external reliability?
- test retest
- inter observer/rater reliability
198
What is the test retest method?
- repeat the study
- test correlation strength between both sets of results
199
How do you test inter observer/rater reliability?
- have multiple researchers carry out the study
- test correlation strength between the sets of data
200
How do you improve reliability in observations?
- improve observer training
- pilot studies
- operationalise behavioural categories
201
How do you improve reliability of interviews?
- structured interviews
202
How do you improve reliability of questionnaires?
- use closed questions
- use an already established questionnaire
203
How do you improve the reliability of an experiment?
- standardise the procedure
- use already established tests
204
What is validity?
Data that is truthful and accurately reflects natural behaviour
205
What is internal validity?
Whether the change in the DV was caused by the IV only
206
What is external validity?
Whether the results can be generalised
207
What are the types of external validity?
- ecological validity
- mundane realism
- population validity
- temporal validity
208
What is ecological validity?
Whether the findings can be generalised to an alternative environment
209
What is mundane realism?
The extent to which a task in the study is similar to real life
210
What is population validity?
The extent to which the sample is representative of the target population
211
What is temporal validity?
The extent to which the findings can be generalised over time periods
212
How do you assess validity?
- face validity
- concurrent validity
213
What is face validity?
Whether the test appears to measure what it claimed to
214
What is concurrent validity?
The extent to which data from a test is similar to an established test
215
How do you improve internal validity?
- demonstrate high levels of control over variables
- random allocation
- randomisation
- standardisation
- counterbalancing
- single/double blind trials
- peer reviews
216
How do you improve external validity?
- replicate the study in multiple settings, samples, time periods and using realistic tasks
217
How do you improve the validity of experiments?
- use a control group to compare to
- single and double blind trials
- standardise procedures
218
How do you improve validity of questionnaires?
- have a lie scale to assess social desirability bias
- ensure participants know all data is anonymous
219
How do you improve validity of observations?
- don’t interrupt/interfere with observation
- operationalise behavioural categories
220
How can you improve the validity of interviews?
- triangulation using lots of sources
- quote participant responses
221
What are the features of psychology that make it a science?
- empiricism
- objectivity
- theory construction and testing
- replicability
- falsifiability
- paradigm shifts
222
What is empiricism?
The idea that factual knowledge only comes from experiences
223
What evidence is there of empiricism in psychology?
- anything gained from experiments, observations etc
- e.g. brain scans
224
What evidence is there of not using the empirical method in psychology?
- subjective methods such as case studies and interviews
225
What is objectivity?
Data should be collected in ways that avoid bias
226
What evidence is there of objectivity in psychology?
- e.g. brain scans in cognitive neuroscience
227
What evidence is there of not using objective methods in psychology?
- case studies
228
What is theory construction and testing?
- forming a general explanation based off of lots of facts
- can be tested using hypothesis testing to find out significance of theory
229
Where is there evidence of theory construction and testing?
- experimental studies as they are analysed afterwards for a significant result
230
Where is there evidence of not using theory construction and testing?
- some theories can’t be tested such as the psychodynamic theory
231
What is replicability?
Using standardised procedures that can be repeated
232
What are examples of replicability?
- studies on conformity have been replicated and found consistent over multiple contexts
233
What are some examples lacking replicability?
- humanistic and psychodynamic theories are hard to be replicated in studies
234
What is falsifiability?
Theories must be able to empirically tested and proved wrong
235
What are some examples of falsifiability?
The use of null hypothesis in hypothesis testing
236
What is a paradigm shift?
When shared sets of scientific assumptions changes to another e.g. Freud’s ideas to behaviourist ideas
236
What are some examples that lack falsifiability?
- psychodynamic and humanistic concepts cannot be proved wrong
237
Why is it argued psychology doesn’t experience paradigm shifts?
The approaches are still used in conjunction and not one is the universally accepted approach
238
What are the stages of a scientific theory construction?
- observation of naturalistic behaviour in the real world
- contstruct a testable hypothesis
- conduct an experiment and gain data
- propose a theory or add to an established theory
239
What is the abstract?
- couple paragraphs at start of report summarising the report
- includes aim, hypothesis, method, sample, major results and conclusion
- allows other researchers to determine if the report is relevant to them
240
What are the features of a psychological report?
- abstract
- introduction
- method
- results
- discussion
- references
241
What is the introduction?
- guide to academic background of the study
- justifies why the research is being conducted
- explains the aim and hypothesis
242
What is the method?
- outlines in detail how the research was conducted
- includes design, participants, materials and procedure
243
What are the results?
- summarises the data collected
- includes the statistical tests
244
What is the discussion?
- explains what the data analysis means
- opportunity to criticise own research
245
What are the references?
- list of other studies that were used to inform the study
246
What is quantitative data?
Data that is in number form
247
What are strengths of quantitative data?
- objective
- can be displayed in graphs, charts and tables
- tends to be more reliable as higher chance of getting the same results
248
What are weaknesses of quantitative data?
- lack detail
249
What is qualitative data?
Data in word form
250
What are strengths of qualitative data?
- rich in detail
251
What are weaknesses of qualitative data?
- subjective
- hard to summarise
- low reliability
252
When is quantitative data used?
- experimental and observational research
253
When is qualitative data used?
- case studies and open questions interviews/questionnaires
254
What is primary data?
The researcher generates the data themselves which answers the research questions
255
What are the strengths of primary data?
- high validity as it answers the direct research question
- high validity as researcher controls the data collection process
256
What are weaknesses of primary data?
- time consuming and expensive
257
What is secondary data?
Researchers use previously collected data from other studies to answer their research question
258
What are strengths of secondary data?
- not time consuming or expensive to collect
259
What are weaknesses of secondary data?
- low validity as not collected to answer that specific research question and they cannot control the data collection process
260
What is a meta analysis?
Collecting and combining secondary data to create an overall conclusion
261
What are the strengths of a meta analysis?
- large sample size
- reduces effect of bias/lack of control as there is so many studies
262
What are weaknesses of a meta analysis?
- has all the weaknesses of secondary data
- biased choice in what studies to include
263
What is meant by a measure of central tendency?
A single value that summarises a set of data by identifying the average
264
What are the 3 measures of central tendency?
- mode
- median
- mean
265
What is the mode?
Most frequent value, data sets can be bi-modal and multimodal
266
What are the strengths of mode?
- not distorted by extreme scores
- helpful for discrete numbers
- only way of giving an average in categorical data
267
What are the weaknesses of mode?
- aren’t always the exact average
- not as sensitive as it doesn’t include all values
268
What is the median?
The central value of
269
What are strengths of the median?
- not affected by extreme outliers
- easy to calculate
270
What are weaknesses of the median?
- not as sensitive as it doesn’t include all values
- if there is an even number the value isn’t one of the recorded values
271
What is the mean?
Mathematical average found by adding all values together and dividing by the number of values
272
What are strengths of the mean?
- all data is included so it is the most sensitive
273
What are weaknesses of the mean?
- can be distorted by extreme outliers
274
What is meant by measures of dispersion?
A single value that summarises the spread of data
275
What are the 2 measures of dispersion?
- range
- standard deviation
276
What is the range?
The difference between highest and lowest values
277
What are the strengths of the range?
- easy to calculate
278
What are weaknesses of the range?
- extreme scores distort values
- doesn’t show if data is clustered or spread out
279
What is standard deviation?
A complex calculation using all data points where smaller numbers mean values are more clustered around the mean
280
What are the strengths of standard deviation?
- includes all values
- provides information about spread of data
281
What are weaknesses of standard deviation?
- extreme outliers distort it
- extremely complex to calculate
282
What is a table?
- shows raw data
- can show measures of central tendency and dispersion
- helpful for interpreting findings
283
What is a bar chart?
- summarises frequency of categorical/nominal data
- the bars don’t touch
284
What are pie charts?
- represents all the data by each wedge being the categories
- size of each wedge is proportional to amount in the categories
285
What is a scattergram?
Shows the relationship between two co-variables
286
What is a histogram?
- displays frequency of continuous data
– bars do touch
287
What is a line graph?
- used for continuous data
- shows the continuous values on the x axis and frequency on the y axis
288
What type of graph/chart displays nominal data?
- bar chart
- pie chart
289
What type of bar/graph shows continuous data?
- histogram
- line graph
290
What type of bar/graph shows the relationship between co-variables?
- scattergram
291
What are the 2 types of distribution?
- normal and skewed
292
What is the shape of a normal distribution?
Bell curve
293
What is the mode of a normal distribution?
Highest/midpoint
294
What is the median of a normal distribution?
Highest/midpoint with equal numbers on either side
295
What is the mean of a normal distribution?
Highest/midpoint as equal numbers of outliers on either side
296
What is the SD of a normal distribution?
- 68% fall within 1 SD
- 95% fall within 2 SD
297
What is statistical infrequency?
How far the score is from the mean
298
What is a skewed distribution?
The distribution is asymmetric
299
What are the 2 types of skewed distribution?
- positive
- negative
300
What is a positive skew?
Highest concentration of data at left side
301
What is a negative skew?
Higher concentration of data at right end
302
Where is the mode on a skewed distribution?
Highest point
303
Where is the median on a skewed distribution?
Where there is 50% on either side (between mode and mean)
304
Where is the mean on a skewed distribution?
Shifted towards the outliers
305
What are the levels of measurement?
- nominal
- ordinal
- interval
- ratio
306
What is nominal data?
Categorical data that is discrete and has no order e.g. birth country
307
What is ordinal data?
Categorical data that has an order e.g. placing 1st 2nd and 3rd in a race
308
What is interval data?
Continuous data that is measured in fixed units e.g. weight and height
309
What is ratio data?
Interval data that has an absolute zero e.g. temperature in Kelvin
310
What is variability?
The idea that even in a well controlled environment there will be some natural variability so researchers use probability yo minimise the chance they reject the null hypothesis
311
What does P = <0.05 mean?
Psychologists accept that 5% of their results are due to chance
312
What does P = >0.01 mean?
1% of their results are due to chance
313
When is a P level of <0.01 used?
When they are replicating a study or attempting to support a controversial theory
314
What is a type 1 error?
When they accept the alternative hypothesis but really the findings were due to chance
315
What is a type 2 error?
When they accept the null hypothesis when there really is a significant difference in results
316
What test would you choose for a test of difference using repeated measures with nominal data?
Sign test
317
What test would you choose for a test of difference using repeated measures with ordinal data?
Wilcoxon
318
What test would you choose for a test of difference using repeated measures with interval data?
Related T test
319
What test would you choose for a test of difference using independent groups with nominal data?
Chi squared
320
What test would you choose for a test of difference using independent groups with ordinal data?
Mann Whitney
321
What test would you choose for a test of difference using independent groups with interval data?
Unrelated T test
322
What test would you choose for a test of correlation with nominal data?
Chi squared
323
What test would you choose for a test of correlation with ordinal data?
Spearman’s Rho
324
What test would you choose for a test of correlation with interval data?
Pearsons R
325
What is the template for significant questions?
- find calculated value
- identify degrees of freedom
- identify significance level (0.05 or 0.01)
- one tailed or two tailed?
- is the critical value more or less than calculated value
326
When do we accept null hypothesis and why?
- if the calculated value is more than the critical value
– because it means there was a more than 5% probability the results were due to chance
327
When do we reject the null hypothesis and why?
- when the calculated value is less than the critical value
- as there is a less than 5% probability the results are due to chance
328
How do you calculate the sign test?
- minus condition B from A
– work out the number of participants excluding participants with the same score
in both conditions
- work out S which is the least frequent sign
- use the table to find the critical value
