Lecture 2 – chapter 2
Lecture notes – Tuesday sept 18th
Descriptive vs correlational studies:
Descriptive – involve observing and classifying behaviour
Eg – Shirley Brice stayed with 300 families – observing differences between
middleclass/lower class much they interacted with children.
In psychology, descriptive/observational studies are usually the first step in a line of research.
Or it can add as a part of a larger research.
Correlational – specifically examining how variables are related to each other, without
manipulating any other variables.
Eg – linking depression and cell phone/computer use. Electronic use sleep deprived
depression. However, it’s unclear what variables cause sleep deprive etc,
Eg – academic success – doing betterhigher self esteem. But we don’t know if there
are any other variables causing it.
It allows researchers to make claims about associations between variables, but cannot make
The third variable problem – specifically given to correlational studies. It occurs when
researchers cannot manipulate the variable they believe is causing changes in another variable
Eg – pre-school and reading skills.
Confound – think of it as a third variable that youre not studying – it seeks into your study. Its
something else aside from the independent variable that still affect results. It provides more
solutions to a problem, being a problem.
Eg – the effects of intoxication on diriving skills. All drunk drivers get smart-cars,
sober people get SUVs. Here the confound is the car, the independent variable
(varies) is the intoxication level. We cannot know whether people are just bad drunk
dirvers, or bad drivers in Smart cars. Focus on data
Good research requires data that is
Accurate – the extent to which the experiemental measure is free from error.
Random error vs systematic error.
Random error – using a stop watch – too fast on some trials, too slow on others. Over
long trials, it would average out.
Systematic error – eg equipment malfunction in stopwatch – 2s slow push on all
pushes, hence wrong results.
Validity – refers to the extent of the data collected addresses the research the hypothesis.
How well are we controlling the variables?
Are we measuring what we’re supposed to be measuring?
Eq – does processing speed increase as people age?
- hypothesis – university students have faster reaction times on the Stroop(colour)
test than elementary school students.
- Our collected data(reaction times from the stroop task) would be a valid way to
address our question
However, if the question was ‘do people enjoy the test more as they get older’ – our data
would not be valid
Constructs- insternal adttributes or characteristics that cannot be directly observed, ut are
useful for describing and explaining behaviour .
Construct validity the degree to which the ind variable and dep var in a study truly
represent the abstract, hypothetical variables in which the research is interested.
Eq – mood manipulators – How will scenes affect moods? show sad scene from lion
king, vs high scene from 21 jump street.
The extent to which my findings providie evidence of causality.
All about our ability to make causal claims.
Fewer variables to worry about in labs, hence confounds are eliminated, but may not work in
the real world.
The extent to which my findings describe what happens in the real world (outside of the lab,
our specific people used, people and situations) It’s all about balancing external validy and internal validity
Reliability – refers to the extent to which a
Inter observer agreement/inter rates reliability – the degree of which independent
observers/judges are coming to the same conclusion. How much do they agree? Would they
code behaviour in the same way?
So in Olympics (judging) – judges who differ (5,6,10), they take away the lowest and
highest numbers to lower the inter-rater reliability
Internal consistency – the degree to which all specific items or observations a multi-item
measure behave the same way. How well the measures correlate with each other. See slide.
High internal consitency – low on one question – low on all questions (or high – high on all
questions) consider love test questionaiore on psyniup.
Temporal reliability/test-retest reliability. The degree to which scores of individual
participants remain stable over time. Say measure of happiness in class, do one test 1 weke,
second week again, very different answers – hence low test/retest reliability.
Evaluating our data
We need to organize it in a meaningful way.
Involves measures of
Central tendancy – finding the single most representative score of data. If describing test
with 1 data, which number would we use. We have the mean, median and mode.
Mean (average) – the artithmetic average of a set numbers. Usually compare means.
Median – the value in a set of numbers that falls exactly halfway between the lowest and the
highest values. 52, 53, 64, 77, 99 – Median is 64. If there is no middle number, average the
middle 2 numbers. Often used to tell income because some make way more, some make a
Mode – the most frequent value. 52, 52, 55, 66, 86 – mode is 52. Differnce from median and
mean, the mode must correspond to an actual score in the data.
Variability – in a set of numbers,how widely dispersed the values are from each other, and
from the mean. Are everyone really spread out, or clustered is my data? (consider grades,
some get below 10%, some 90%, mean is 60%)
Range – difference (delta) between highest number and lowest number (not a good measure,
ignores most scores, but it does say beginning/end). Standard deviation – tells you how far away of the mean each score is. Smaller standard
deviation – clustered around the mean, larger standard deviation – spread out. Shows the
range, but with the amounts.
Scatterplots –graphs that illustrate the relationship between two variables (correlational, such
as beer sales and temperature).
Correlational coefficients have values from -1,0 to +1,0.
Perfect correlation – if 1 degree goes up, 1 beer is sold, the relationship is
perfect/constant. This is positive correlation.
0 = no correlation
Inferential statistics – A set of procedures used to make judgements about whether differences
actually exist between sets of numbers. we want to make claims that go beyond the samåples
of data, extend it out to the population. Whether scores are significantly different
experimental group is different from the observational group. Google this. Are the observed
diffreneces between out experimental groups due to chance variation or do they reflect true
Replicate, revise, report.
Replication – may be exact. Want to replicate the result.
- Conceptual replication – not identical experiment, you vary the variables a little to see effect
Consider mood manipulation – try 1 you show happy faces vs sad faces, try 2 you
operationalizing variable by having them write their happiest memomry before the
Revise – think about if my hypothesis was supported, think about what it means. What are the
Report – write up or present my results, share it. Scientific method : LEARN
HOMER Chapter 4, the Mind and Consciousness
Consciousness is our subjective moment to moment experience of the world (internal and
external. Whatever part of your brain is activated at a particular moment.
There are limits – we cannot be aware of everything.
The brain can process (and act on) info that you’re not aware of. Consider blind people – they
cannot see things, say you hold a face in front - make them guess if it’s happy or sad. They
guess better than chance. This means that even though they aren’t aware of seeing, parts of
the brain are receiving information making them able to guess. Same with dots moving to left
Subliminal messages – any information that we aren’t aware of having received/outside our
conscious awareness (flash pictures, associations). Derren brown priming video
Much of behaviour happens without our intention or awareness – and we act pretty smart. Our
unconscious mind can make sense of things, whereas it wont overthink. When we don’t think
that we’re thinking about it, and wake up next morning with a decision, unconscious can have
decided for you. Verbal overshadowing – hard to explain a lot of decisions, and trying to
explain it often fucks it up (getting insecure).
Split brain – the corpus collosum is cut. Can prevent spreading from seizures. Now the 2
hemisphere aren’t speaking to each other. They have their own consciousness, thoughts and
perceptions. Images of left visual go to right hemisphere, and opposite. Left hemisphere
controls right arm, and right hemisphere controls left arm. Left hemisphere is predominant for
speaking (left frontal lobe) (what about women???). Right hemisphere is good for spatial
relations (what is this???).
The left hemisphere doesn’t know what the right hemisphere has seen, so it comes up with an
explanation, by interpreting the left hands (right brain’s) response.
Interpreter – left hemisphere process – finding relationship/patterns/explanations to make
sense of things.
Right side – recognizing faces – adaptive (consider evolution, needed to read expressions etc).
Fusiform face area (FFA), located at the intersection of the occipital and temporal cortices and
is usually larger on the right side.
People can have their entire hemisphere removed, and the other side adapts. If pass-out drunk what kind of brainwaves?
Beta waves- alert awakeness.
Alpha waves – resting/relaxing, right before sleep.
Stage 1 Theta waves early sleep (you don’t know you’re sleeping)
Stage 2 Theta waves genuine sleep. There are sleep spindles (burst of activity) which
they think of the brain working hard to turn off the external stimulation and sleep. K-Complex
Stage 3+4 large delta waves deep sleep.
During rem sleep rapid eye movements paralysis of motor system and dreaming
(bizarre, illogical and emotional). Arise from activiation of emotion, motivation, reward and
visual centres of the brain. You also remember more dreams from REM sleep.
During non-REM sleep more boring dreams (day to day activities).
Adaptiveness of sleep:
Purpose of sleep:
- restorative sleep growth factor hormone released, restore yourself for the next day
- Circadian rhythm theory stay inactive during the day when we are most vulnerable
(shitty nightvision stay quiet and in rest)
- Facilitation of learning theory learning is about creating new neural connections.
These connections are strengthened and consolidated during sleep. Especially if you
dream of the situation (school/tasks), this helps you learn the information.
Alcohol may help you fall asleep faster, but it messes up the sleep cycle (REM/non-REM)
and the quality of sleep you get.
- Lightens my sleep (might not rea