PSYC210

inferential statistics

used to decide about the population based on observations on the sample

positive correlation on a graph

tilting upwards either to the left or right

negative correlation on a graph

as one variable increases, the other variable decreases

regression analysis

Statistical method used to determine what the relationship between variables and the strength of the relationship. - fits a line that best fits the data

Y = a + (b x X) for regression analysis

Y = Y axis

a = intercept (where the line crosses the Y axis

b = slope of the line

X = X axis

population parameters

mean µ

standard deviations σ'

statistical sample

mean x̄

standard deviation ‘s’

3 steps to construct a sample distribution

1. make a guess about population frequency distribution, hypothesize these means.
2. take a random sample
3. decide if the same came from the guessed population

significance level (alpha level)

the probability value that defined the boundary between rejecting or retaining the null hypothesis

by increasing the power

increase in alpha and increase in n

assumptions of a t-test

1. the random sample comprises interval or ratio scores
2. the distribution of individual scores is normal
3. standard error of the mean is estimated using SD computed from the sample

qualitative research

people and context, collected through interviews and observations, non-numeric data.

what does qualitative data involve

quotes or images, non-numeric, primarily involves ‘the human experience’.

quantitative research

researching using patterns of numbers, statistics

does qualitative research generally have a hypothesis

without a hypothesis

does qualitative research form hypotheses inductively or deductively

inductively

inferential tests

central limit theorem t-test

central limit theorem sampling distribution

* assume
* normal population distribution with µ and σ' (mean and sd)


* take
* repeated samples of size n
* plot
* x̄ of each sample

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significance level or alpha (a) level

the probability value that defines the boundary between rejecting or retaining the null hypothesis (h0)

* level usual at 0.05 (or sometimes 0.01)

p < alpha → rejection of H0 (null hypothesis)

region of rejection

the proportion of area in a sampling distribution that represents the sample means that are improbable if Ho (null hypothesis) is true

type I error

rejecting the null hypothesis when it is true

p = alpha

type II error

retaining the null hypothesis when it is false

p = B (beta)

understanding the relationship between type I and type II errors

* type I and type II errors are mutually exclusive
* if you have one type, you can NOT have the other
* changes in one type of error have an effect on the other type of error

minimising type II errors

* reducing B and increasing power (1 - B)

so that we can reject the null hypothesis when it is false

increasing alpha

1. reduces the probability of a type II error
2. increases power (1 - B)

(increases the probability of rejecting the null hypothesis when it is false)

single sample t test steps

1. calculate the observed t using the estimated standard error of the mean
2. determine the df
3. look up the critical t in the t-table with the appropriate df (and alpha)
4. if observed t __is greater than or equal to__ the tabled value then reject the null

null hypothesis

there will be no relationship between the two variables

T-test results

the further apart the means are the more reliable - how wide the disruption from the top of each peak. if lower than 0.05 then it is probably a difference

multiple regression

predicting one variable based on multiple predictor variables

neurons

connected and have many dendrites

axons

conduct electrical signals, surrounded by myelins

myelin

insulating layer forms around the nerves. Is a major factor in determining the MR signal and contrast

grey matter

composed of cell bodies around the edge of the brain

white matter

comprised of axon projections surrounded by myelin

MRI analysis

MRI is:

* noisy
* variable/configurable

analysis is:

* based on stats
* has many options/alternatives
* has more than one ‘right’ way (but many wrong)

what does a diffusion MRI measure in scientific terms

Average direction of axons in voxel (3d chunk of the brain) and axonal integrity (how much overall does the water diffuse)

tractography

a method for tracing white matter pathways in the brain to investigate connectivity

Cerebrospinal fluid

the fluid in and around the brain and spinal cord - cushions the brain

corpus callosum

the large band of neural fibres connecting the two brain hemispheres and carrying messages between them.

structural MRI

images gross brain activity, useful for visualising lesions, pathologies or nuclei

What can you look at in the brain with a structural MRI?

Tissue types, subcortical structure and shape and GM changes

structural MRI limitations

* does not directly measure tissue type
* absolute values are not the same over scans or sessions
* does not always distinguish bone from air
* single image does not show all pathologies

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diffusion MRI

based on movement of water in the brain, gives most information about axon directions in the white matter. (non-invasive)

how is a diffusion MRI useful

can get information about microstructures by looking at the direction of the water.

diffusion MRI limitations

* does not measure axon size or density
* does not measure single fibers
* more difficult to conduct pulsing brain areas
* sensitive to fast imaging artefacts
* may distort images

structural vs diffusion MRI

* Structural takes 5 mins for one photo
* Diffusion takes total of 5 mins for 100-300 images
* Diffusion MRI has lower resolution

Why do Diffusion MRIs focus on White matter not gray matter?

grey matter is mainly unorganised cell bodies where the water does not flow in a specific way

functional MRI

looks at brain activity when a person is doing a task

PET scans

measure brain metabolism directly, can use radioactive tracers to indicate particular areas of the brain.

EEG

measures electrical brain activity directly, has faster temporal resolution compared to functional MRI

Rubenking & Bracken (2018)

quantitative binge-watching study, as age went up the binge-watching went down

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Who had a higher rate of binge watching in the rubenking and bracken study?

Students ( age had a significant negative relationship with binge watching)

Steiner & Xu (2020)

qualitative binge-watching study motivations for binge watch themes

main themes in Steiner and Xu study

* relaxation
* catching up
* sense of completion
* cultural inclusion
* improved viewing experience

reflexivity

analyzing and critically considering our own role in, and effect on, our research - environment plays a role in how we react to info.

ontology

views on human reality

Ontology- realism

quantitative research, the idea that there is one true reality independent of perception

ontology relativism

qualitative research, the idea that peoples realities differ relative to perception

epistomology

what we know and how we know it

epistemology- positivism

knowledge and meaning are waiting to be discovered and then it is considered true until disproven through research

epistemology- social constructivism

knowledge and meaning are being generated by attempts to explain the human world including research

what is a strong realism

there is one “true” reality (independent of perception).

what is strong relativism

people’s realities differ (relative to perception)

the view that our knowledge of reality is never a simple reflection of the way the world actually is, but is sustained through subjective social processes.

what is positivism

knowledge and meaning is waiting to be discovered and is then considered “true" until disproven (through research)

what is social constructionism

knowledge and meaning is being generated by attempts to explain the human world (including research)

key points of data gathering and analysis

interview questions need to be planned, research relies on trained researchers.

what does data gathering and analysis look like in quantitative research

mostly asking closed questions of large samples to test very specific hypotheses

what does data gathering look like in qualitative research

mostly asking open-ended questions with specific groups of people to explore their experiences

how do you generate a research question

1. state the goal
2. define the population sample
3. define the setting
4. identify the primary topic
5. be precise enough to be feasible

what is a theme

a patterned response or meaning within the data set

what can a theme also be referred to as

a category or a dominant discourse

what is a research interview

a systemic social enquiry

what are the two main types of interview questions

closed questions and open-ended questions

what are closed questions

imply fixed answer choices

what are open-ended questions

invites expansion

what is a structured interview

* survey type involves closed questions
* fixed topic and order of questions
* very clear roles-being read a questionnaire
* expansion allowed only if pre-defined=branching

what is a unstructured interview

broad research topic, interview is open and general and framed as exploratory. *structure can be added as information is gathered*

what is a semi-structured interview

* semi-defined research topic
* open-ended questions
* question order can vary
* involves asking open questions or elaborating on closed questions.

which structure should be used for quantitative research

structured interviews

which structure should be used for research development and pilot studies

unstructured interviews

which structure should be used for qualitative research

semi-structured interviews

one-on-one interviewing

most common source of qualitative data

what does discourse mean

patterns of language about a concept

what does identity mean

notions of self that draw upon available discourses

De Visser and Smtih (2006) key concept

hegemonic masculinity = expected patterns of behaviour among men

what was De Visser and Smith (2006) research questions?

* how do men come to identify with a particular discourse of masculinity? (broad focus)
* what does it feel like for a man to reject hegemonic masculinity and manage man alternative masculine identity? (narrow focus)

Who was De Visser and Smith (2006) participants

one participant (case study)

what was De Visser and Smith (2006) method

semi-structured interviews (some planned questions)

* prompts about how he spends his free time


* analysis was transcribed and entirely focused on what an be learnt from Rahul.

what were the three themes in De Visser and Smith’s study

1. difference from others
2. why he doesn’t drink
3. being sporty makes him masculine enough

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what were the conclusions in De Visser and Smith’s study

1. Rahul worked with and against elements of masculinity in creating his identity as different from other men

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2. provides insights into how hegemonic masculinity might influence health-related behaviour such as drinking

what are the critiques of De Visser and Smith’s study

1. Was Rahul asked for feedback on the analysis?
2. how masculine did the interviewer portray himself?

what is a focus group

an information discussion among selected individuals about specific topics. applying interview techniques to groups (n=3+)

pros of focus groups

* pre-existing friends can talk about shared experiences
* unknown participants can provide deeper explanation
* a good interviewer steers the balance of talking
* close to a certain type of natural group interaction

cons of focus groups

* pre-existing friends can lead to assumptions and tensions
* unknown participants forming new relationships
* who dominates the discussion?
* too many ppl?
* not a natural environment (talking over each other)

which studies started modern ethics talk

Stanford prison study- harm

Milgram electric shock studies- deception

what are ethics committees used as?

a check point for being fully prepared

what was the purpose of Lyons and Willott’s (2008) study

to investigate how groups of friends of young men and women talk about their alcohol consumption

what were Lyons and Willott’s research questions

1. do women discuss drinking in different ways to men within the friendship groups?
2. how is women’s drinking more generally discussed within the the friend groups?

what was the method of Lyons and Willott’s (2008) study

Eight focus groups-facilitated interaction

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focus group questions:

\-typical drinking behaviour

\-where? and who with?

\-how often and how much?

\-ideal night out?

\-women’s drinking?

\-behaviour while drinking?

\-drinking culture in New Zealand?

what was the analysis of Lyons and Willott’s (2008) study

Discourse was applied:

\- How meanings are reproduced in talk

\- Particularly attuned to inducing or getting the participants to link, talk about drinking and ideas about gender

\- Transcribed, read twice and listened to again and then started the detailed analysis

\- Focus on talk about gender and the inconsistencies