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The rules and mediums. Dr. Anna Johnson Week 2 The rules and mediums Thursday 8 th February 2007.
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The rules and mediums Dr. Anna Johnson Week 2 The rules and mediums Thursday 8th February 2007
Students please note: I have included quite a few links to web pages that will help define and explain concepts in this (and future weeks) slides. Therefore, for the links to work you need to be on-line and have access to the internet.
Today • Types of measurements • Sampling and recording rules • Ways to collect behavior: pros and cons
Types of measure • Latency • Measured in units of time (sec., min., hours) • Is the time from some specified event • Ex. Suckling in piglets (every 40 minutes for 5 minutes of time) • Period of observation is usually limited • Each individual usual tested more than once
Types of measure • Frequency • Number of occurrences of the behavior pattern per unit of time • Rate of occurrence • Ex. Feeding bouts of cattle • Ex. A rat presses a lever 60 times during a 30 min -1 recording session therefore the frequency of lever pressing is 2 min -1
Types of measure • Duration • Length of time for which a single occurrence of the behavior lasts • Actual units or as a percentage • Ex. A kitten starts to suck and stops 5 minutes later the duration for that suckling period was 5 minutes • Total duration – again MUST note the TOTAL time you were watching that animal
Types of measure • Duration • Mother and her infant were observed for 60 minutes • During which suckling occurred five times • Individual suckling periods lasting 3, 10, 1, 1 an 1 minutes respectively • Therefore: • Duration of suckling = 3 , 10 , 1, 1 and 1 min • Total duration of suckling = 16 mins per 60 min • Proportion of time suckling was 0.27 (16/60) • Mean duration of suckling was 3.2 min (16/5)
Latency : Frequency : Duration Frequency is 3 / t per unit of time The total duration is a + b + c units of time The mean duration is (a + b + c) / 3 Red bars represent three successive occurrences of a behavioral pattern i.e. nursing in piglets during an observation period of “time” or t t 0 1 2 3 Latency a b c I.e. it took 20 mins for the behavior to happen Time (t)
Types of measure • Intensity • Difficult to measure • No universal definition • Intensity - Ex. Vocalization or limping
Intensity Discrete acts (lines) i.e. leg lift or head bob = 19 21 6 t 0 t1 t2 t3 Local rate = Total no. of occurrences (t1 + t2 + t3… + tn)
Intensity: Gait • Score 1: Normal Gait • Normal Gait Clip • Score 2: Mildly lame • Mildly Lame Clip • Score 3: Moderately lame • Moderately Lame Clip • Score 4: Lame • Lame Clip • Score 5: Severely lame • Severely Lame Clip It takes a little time to open up – click OK when is talks about viruses it is fine…. Thanks to the University of Edinburgh for the clips
Student question: How would you attempt to score gait intensity as seen from these examples?
Events vs. states • Events • Relatively short duration • Discrete body movements • Biting, kicking • Vocalizations
Events vs. states • States • Relatively long duration • Ex. lying
Students Be prepared… • 1. Students – I want all of you to: • Write down on paper the following headings: • Events • States • Next write down under each of these heading five behavioral states and five events • You will ALL be asked in class to ID at least one behavioral state and event • Success in answering will give you your participation points • Questions? E-mail me at johnsona@iastate.edu
Hierarchy of sampling and recording rules Sampling rule Ad libitum Focal sampling Scan sampling Behavior sampling Recording rule Continuous recording Time sampling Instantaneous sampling One-zero sampling
Ad libitum sampling • No constraints on the duration of the observation period, how many individuals are observed, or what data or observations are recorded • Usually results in copious field notes
Students: Question What could be a major problem with this method of sampling behavior?
Focal sampling • Observing a single individual of a particular species, usually for a specified period of time • Often used to study specific behavior patterns • The observer records all instances of the behavior under study within a given time interval
Students: Question What could be a major problem with this method of sampling behavior?
Scan sampling • Observer censuses a large number of individuals and records their behavior at the instant they are observed • Must be done relatively quickly • Usually restricted to broad categories of behavior such as "foraging", "flying", or "resting” • May take a few seconds or several minutes
Students: Question What could be a major problem with this method of sampling behavior?
Behavioral sampling • Chain or sequence of specific behavior patterns that are generally exhibited in a particular sequence • Observation period does not have an arbitrary beginning and end, but rather begins when the observer thinks the behavioral sequence begins, and ends when the observer thinks the sequence ends
Students: Question What could be a major problem with this method of sampling behavior?
Continuous • Exact and faithful record of what behavior • Measuring true frequencies and durations and the time when behaviors start and stop
Time sampling • Instantaneous • One zero
Total observation period = 30 minutes This gives 120 Sample Points (60 seconds [1 minute] / 15 seconds = 4 x 30 minutes = 120) Start Time Sample Interval of 15 seconds
Student Question: Is instantaneous sampling suitable for recording discrete events of short duration?
Question to ask: what are you interested in collecting – this often dictates what medium (s) you need to use….
Recording medium • Film or video recording • Written or dictated verbal descriptions • Automatic recording devices
Line drawings from photographic stills that were taken in rapid succession Dawkins and Nicol, 1989
Written or dictated verbal descriptors RV can act as a blind – why might be this important?
Spreadsheet for FOCAL More mutually exclusive these are the easier the data can be recorded! Animal: One Continual recording so have excel sheets made to go and would check off each behavior, posture and location as it occurred and note the time – so I know how long they are performing what….
One – Zero Sampling Is the pig eating?
Blinds / Hides • Behavior of the animal • Reaction to strange objects • Spatial distribution – can you see the animals! • Observational capacity • Number and size of openings for seeing . filming • Permanence • Can it be permanent for several weeks / years? • Is it set in one spot or moveable? • Climatic conditions • With stand what weather extremes? • Winds • Comfort to be in!
Binoculars Lehner, 1979
Voice • Go to: • http://source.journalism.indiana.edu/science/20060427animalfarm/ • Scroll down and click on • Hear an audio clip from Jen Miller talking about the "Animal Behavior Farm” – you will need speakers!
Vocalization examples • Recent experiments on food calling have concentrated on the responses of signal receivers • Chicken calls • Scroll down to Food Calls • Click on the play button on the still frame picture titled FC_Playback (note it takes time to fire up and you need Quick time) • The hen approaches the loudspeaker, which is behind a screen at the right-hand end of the cage, and begins looking downward and pecking at the substrate • These anticipatory feeding movements are much more frequent when food calls are presented than when the hens are played either ground alarm calls (which are structurally similar), or contact calls (which are produced under similar social circumstances)
Challenges with tape • Tape runs out • Real time being difficult to keep • Getting the information off the tape and making it useful • Recording / talking may disrupt the animals
Hand held Computers Palm Pilot
Students Be prepared… • 1. Students – I want all of you to: • Write down on paper the following headings: • Film or video recording • Written or dictated verbal descriptions • Automatic recording devices • Next write down under each of these heading two positives and two negatives associated with using these types of recording mediums • You will ALL be asked in class to ID one + and one – for one of these mediums • Success in answering will give you your participation points • Questions? E-mail me at johnsona@iastate.edu
Reliability = Reproducibility of the Measurements Error of apprehending Observer error Observer bias Inter (more than one) and Intra- (you) observer reliability Observer effect Error of recording Computational error – results (analysis)
Student Question: How can we improve inter and intra-observer reliability?