Publications by Bluecology blog

Using R and power analysis to inform experimental design

02.11.2019

Using R and power analysis to inform experimental design A collaborator once asked me: “can you do that thing where you take a little bit of data and model it up to make lots more data?” Does it sound suspicious to fake a lot of data from a little bit of data? It depends on the context. Making up data is totally appropriate if you want to do ...

8054 sym R (1855 sym/9 pcs) 4 img

Three ways to calculate distances in R

07.02.2020

Three ways to calculate distances in R Calculating a distance on a map sounds straightforward, but it can be confusing how many different ways there are to do this in R. This complexity arises because there are different ways of defining ‘distance’ on the Earth’s surface. The Earth is spherical. So do you want to calculate distances around ...

4562 sym R (1516 sym/11 pcs) 10 img

Spatial predictions with GAMs and rasters

18.02.2020

Spatial predictions with GAMs and rasters One powerful use of GAMs is for interpolating to unsampled locations. We can combine GAMs with raster package to conveniently predict a GAM model to places we have not got data. Simulate some spatial data We’ll simulate some spatial data based on rasters. There are two spatial covariates, x1 and x2. We ...

3504 sym R (3773 sym/10 pcs) 14 img

A case against pipes in R and what to do instead

20.04.2020

A case against pipes in R and what to do instead Pipes (%>%) are great for improving readibility of lengthy data processing scripts, but I’m beggining to learn they have some weaknesses when it comes to large and complex data processing. We are running a number of projects at the moment that require managing and wrangling large and complex data...

5060 sym R (2931 sym/16 pcs)

How much has the data informed your isotope mixing model

24.04.2020

How much has the data informed your isotope mixing model? The contributions of different food sources to animal diets is often a mystery. Isotopes provide a means to estimate those contributions, because different food sources often have different isotopic signatures. We would typically use a Bayesian mixing model to estimate the proportional con...

8379 sym R (4650 sym/12 pcs) 6 img

Time sinks for data wrangling

30.04.2020

Time sinks for data wrangling Estimating the time it will take to complete a project is an important part of being a successful PhD student, researcher or consultant. A major time sink on many analytical projects is data wrangling. Often the wrangling can take longer than the analysis. Here’s some good questions to ask yourself and your collabo...

5408 sym

Universal inference in R

08.07.2020

Universal inference in R When we perform a statistical test we’d like to have confidence what the Type I error rate is what we say it is (rate of false positive findings). Often scientists choose a rate (AKA ‘alpha’) of 0.05 for rejecting the null hypothesis. We’d like some guarantees that our statistical test will actually have a type I ...

4208 sym R (2235 sym/11 pcs)

Correcting for confounded variables with GLMs

03.09.2020

Correcting for confounded variables with GLMs General (and generalized) linear models can be useful for analyzing field data, where sampling is often distributed unevenly across different environmental gradients or treatment groups. They help us correct for confounded gradients and discover effects that are hidden in plots of raw data. For instan...

4811 sym R (2266 sym/12 pcs) 10 img

New course on preparation and graphing of biological data in R

28.09.2020

New course on preparation and graphing of biological data in R We’re running a short online introduction to data preparation and graphing. The course will cover the basics of pre-processing data, including common data wrangling routines. We will use real world data from the Reef Life Survey to demonstrate these tools and calculate some common s...

2707 sym

R workshops in Brisbane 2021

25.10.2020

R workshops in Brisbane 2021 Our annual series of popular R workshops is on again between 5th and 12th February 2021, in person at the University of Queensland. Over the past 5 years we’ve successfully trained hundreds of academics, researchers and students. There are 4 courses that range from introductory to advanced and focus on applications...

1232 sym