week 3 Flashcards
What are the two types of validty
Internal validity
Construction validity
What is internal validity
is the degree of confidence that the causal relationship you are testing is not influenced by other factors or variables
What is construct validity
concerns the extent to which your test or measure accurately assesses what it’s supposed to
What is extraneous variables
Not being investigated that has the potential to affect the outcome of a research study
What is a confounding variables
related to both the supposed cause and the supposed effect
it can be difficult to separate extraneous variable and independent variable
What is variance
variability of data set
What types of variance
treatment variamce
error variance
What is treatment variance
difference due to what we’ve done
What is error variance
differences due to other variables
What are the two potential effects
Ceiling effects
Floor effects
What is the ceiling effects
the task is too easy
What is floor effects
the task is too hard
How trials effect measurement sensitivity
Too few trial leads to a more insensitive measure
Too many trials can lead to fatigue
We can also use precise equipment
What is the simplest fix for extraneous variables
Randomly assign them to groups as extraneous variables are more balanced out
What is standardisation and why do we do it
What- making the method and procedure controlled and precise
Why- minimises possibility of extraneous variables
How can we standardise procedures
We can use computers as stimuli and instructions are presented and displayed in the same way each time
What is the difference between confounding variable and extraneous variables
confounding variables differ systematically with aspects of the design
What is the biggest threat to a within participant design
Order effects
What is order effects
Changes in behaviour because of ‘when’ a certain condition is completed
What are the types of order effects
Practice effects
Fatigue effects
Habituation
What are practice effects
participents likely to get better at a task each time they do it
What is fatigue effects
if there are a number of conditions, participants may get tired or bored which will affect performance
What is habituation
participants may become less sensitive to a stimulus through repetition
How can we solve order effects in a within-subject
Counterbalance
What is counterbalancing
It is were there the participants are in different groups and the go through the conditions in different orders
When can’t we do counterbalances
when there is 24 or more orders
What can we do if we can’t counterbalance
Partially counterbalance Latin-square design
What is a practice trial
A trial done before the experimental trial therefore anything can be adjusted before it to make it more accurate
What is and why do we do randomisation
It helps eliminate systematic bias
presents the individual trials in a random order
When do we many use between-participants
to see the effect of intervention or treatment
What are the parts of between-studies
Pre-test
Experimental treatment
Post-test
What is a Pre-test
the observation or measure before the intervention
What is a experimental treatment
the different interventions or conditions
What is a post-test
the observation or measure after the intervention
What is Maturation effects
participants behaviour changes over time naturally
What is history effects
something changes about the participant circumstances that influences the variable
What is testing effects
merely having been tested before may have changed how they do on the post-test
Why do you use a control group
to show that the iv does influence the DV and it is not other factors
What are the types of control groups
Passive
Active
Waitlist
What is a passive control group
participants do nothing/a meaningless alternative task, whist those not in the control conditions go through the manipulation
What is a active control group
Participants do something that they could reasonably assume might have an effect but the researchers assume doesn’t
What is a waitlist
participants are waiting to take part in the intervention/experimental conditions, and believe that they will be at some point
What is attrition
participants starting but not completing the study
What is differential attrition
when people leave one condition or treatment more than any other
What is a longitudinal design
participation occurs across different sessions with significant time intervals
Differential attrition is an issue for these studies
What is matched groups
where participants are matched on a third variable like age or IQ and then are split into each group so that it effect both groups negating the effects
What is a pilot studies
used to spot issues before we do the real trials so that problems can be picked up and fixed e.g. unclear instructions, floor/ceiling effects and more
