J-Cleeland / ActGeo

A series of functions designed to resample and analyse geolocation derived activity data.
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resampleAct does not account for 6 second conditional state change #1

Open J-Cleeland opened 5 years ago

J-Cleeland commented 5 years ago

The aim of resampleAct is to make GLS activity data in Method 1 comparable to Method 2.

Method 1: samples for wet status every 3 seconds and records the start time and duration (in seconds) of every state change that lasts 6 seconds or more. Models: MK7 & MK19

Method 2: sample for wet/dry status every 3 seconds and make a record of the total number of samples wet every 10 minutes Models: MK5, MK9, MK10 (S), MK13, MK14 (S), MK15, MK18H, MK18L

Currently the function does not account for the 6 second conditional state change of MK7 & MK19 loggers.

J-Cleeland commented 5 years ago

MK7andMK19GLS_activity

Given the distribution of the duration of wet samples from 14 different tags deployed on Grey Petrels, do we expect a large amount of wet samples <6 seconds are excluded when using Method 1, but which would be recorded as a wet sample and therefore included when using Method 2?

J-Cleeland commented 5 years ago

Using the activity data from 14 GLS tags deployed on Grey Petrels I have determined the daily proportion of time wet and number of take-offs/landings (wet to dry/dry to wet state changes) using the data format of Method 1 and applying no changes, removing wet samples < 6 secs, and resampling Method 1 into Method 2. Here you can see that removing short bouts (< 6 secs) on the water does not really affect the overall time spent wet, but greatly affects takeoffs/landings.

Takeoffs and landings for Method 2 have been calculated using the following conservative approach:

A wet bout is any period where activity >0, and a dry bout is any period where activity = 0. So for the wet bouts, where activity ranges from 1-200, there can be many take-offs and landings, but a landing has to be a value between 1 and 200 that follows a value of 0.

GLS_wet_bouts