Experimental Design of Behaviour Projects Flashcards
Three ways of describing behaviour
Structure, consequences, spatial relation
What does it mean to describe a behaviour using structure
Appearance, physical form or temporal patterning (timing) of the behaviour
Described in terms of subjects posture and movements
What does it mean to describe a behaviour using consequences
The effects of the subjects behaviour on the environment, on other individuals, on itself
What does it mean to describe a behaviour using spatial relation
Relation to features of the environment or to other individuals (landmarks)
Position is important; not so much what subject is doing
e.g. approach or leave
Three guidelines to choosing categories (types of behaviours) for projects
- Enough categories to describe the behaviour in detail
- Define each category precisely
- Categories should be independent of one another
How do behavioural hypotheses change over time
Tend to initially be broad, narrow down as more is discovered
What are the four types of behaviour measures
Latency
Duration
Frequency
Intensity
What is the latency measure? E.g.?
Measured in units of time
Time from some specified event to the onset of the first occurrence of the behaviour
e.g. a ball is placed in pen at time “0,” length of time for animal to approach ball is noted
What is the frequency measure
Measured in reciprocal units of time
Number of occurrences of the behaviour pattern per unit time
Measures rate of occurrence
What type of recording do we use in latency, frequency, duration
Latency = continuous
Frequency = continuous
Duration = time sampling or continuous
What is the duration measure? Two types?
Measured in units of time
Length of time for which a single occurrence of the behaviour pattern lasts (bout length)
Total duration or mean duration
total duration vs mean duration
Total = total length of time for which all occurrences of a beh lasted (proportion of observation period)
Mean = mean length of a single occurrence of the behaviour pattern (record duration of each, calculate mean)
What is the intensity measure? E.g.?
Judgement of the intensity or amplitude of a behaviour pattern
e.g. weight of food eaten, number of prey captured, distance traveled, how loud a call is, how high they jump
What type of behaviour is measured by intensity, frequency, duration and latency?
Quantitative behaviours
Event vs state
Event = beh patterns of short duration (discrete body movements, vocalization) approximated as points in time
State = beh patterns of long duration (body postures, proximity)
What measure do we use to measure events? States?
Events = frequency
States = duration
Most important thing to make sure when marking individuals
It does not affect the behaviours you are trying to observe
If you can’t say it doesn’t then don’t use it as marking (could be a confounding factor)
Group vs parties
Group = association whose composition is known (know all the animals in the group)
Parties = aggregations whose membership is uncertain
What is reliability? vs validity (with regards to behaviour measures)
Reliability = good measures (inter observer reliability = all observers code the same beh as being the same)
Validity = right measures (are you measuring what you think you are measuring)
How do we check the quality of our measurements before data collection
Reliability and validity
Within observer reliability vs between observer reliability
Within = observer consistency, extent to which single observer obtains consistent result when measuring the same thing on diff occasions
Between = extent to which two or more observers obtain similar results when measuring simultaneously (>90%)
What is Kappa coefficient
Want >90% between observer reliability
What factors affect reliability
Practice and experience
Frequency of occurrence (fast/rare behaviours missed unless recorded)
Observer fatigue
Adequacy of definitions (drift with passage of time, observer unconsciously “improves” definition
What is the pooling fallacy
Treating repeated measures of the same subject as though they were independent of one another
Additional measurements from same subject do not substitute for additional subjects
What can affect the independence of the measures
The pooling fallacy
Group effects
Non-independent categories
Confounding factors
Pseudo-replication
What is group effect
Behaviour of one animal affect beh of other
Beh may be similar amongst related individuals
Social interactions between members of group can lead to problems of independence
Within-group variation must be = to between-group variation
What is wrong with non-independent categories
Important to make sure behavioural measures are independent of each other
Causes problems in interpreting associations btw measures
Sleeping is negatively correlated with being awake
What are confounding factors
Difficult to vary one condition without varying something else
Make sure other factors did not affect our results, or randomize
What is pseudo-replication
Experiment may be limited in scope because only a restricted conclusion may be drawn from results
E.g. of pseudo-replication
Many piglets may respond the same way to one tape recording of vocalizations, but they may of responded differently to another tape recording that is thought to be the same but is subtly different
What are ontogeny studies
Cross-sectional research: studying different individuals at each age (disconnected animals, faster/more data)
Longitudinal research: measuring the individuals repeatedly over time (follow one individual, see how life experiences affect beh)
What are choice tests
Test differential responsiveness or preference
Downside of simultaneous choice tests
Simultaneous presentation of test stimuli may be distracting to subject
Subject may be “trapped” by first choice
May need to include a blank choice
