Wavelet spectral testing: application to nonstationary circadian rhythms

03/26/2018
by   Jessica Hargreaves, et al.
0

Rhythmic data are ubiquitous in the life sciences. Biologists need reliable statistical tests to identify whether a particular experimental treatment has caused a significant change in a rhythmic signal. When these signals display nonstationary behaviour, as is common in many biological systems, the established methodologies may be misleading. Therefore, there is a real need for new methodology that enables the formal comparison of nonstationary processes. As circadian behaviour is best understood in the spectral domain, here we develop novel hypothesis testing procedures in the (wavelet) spectral domain, embedding replicate information when available. The data are modelled as realisations of locally stationary wavelet processes, allowing us to define and rigorously estimate their evolutionary wavelet spectra. Motivated by three complementary applications in circadian biology, our new methodology allows the identification of three specific types of spectral difference. We demonstrate the advantages of our methodology over alternative approaches, by means of a comprehensive simulation study and real data applications, using both published and newly generated circadian datasets. In contrast to the current standard methodologies, our method successfully identifies differences within the motivating circadian datasets, and facilitates wider ranging analyses of rhythmic biological data in general.

READ FULL TEXT

page 4

page 19

research
05/19/2020

Multiscale modelling of replicated nonstationary time series

Within the neurosciences, to observe variability across time in the dyna...
research
02/04/2019

Non-decimated Complex Wavelet Spectral Tools with Applications

In this paper we propose spectral tools based on non-decimated complex w...
research
03/02/2019

Non-decimated Quaternion Wavelet Spectral Tools with Applications

Quaternion wavelets are redundant wavelet transforms generalizing comple...
research
12/19/2018

Spectral Inference under Complex Temporal Dynamics

We develop unified theory and methodology for the inference of evolution...
research
08/07/2019

Wavelet Spectra for Multivariate Point Processes

Wavelets provide the flexibility to detect and analyse unknown non-stati...
research
12/05/2019

Bayesian Functional Mixed-Effects Model with Gaussian Process Responses for Wavelet Spectra of Spatiotemporal Colonic Manometry Signals

Objective: We present a technique for identification and statistical ana...
research
07/22/2020

Testing display suitability for presenting mean-modulated flicker in clinical assessment and experimental studies of visual systems

Mean-modulated flicker – wherein luminance increments and decrements of ...

Please sign up or login with your details

Forgot password? Click here to reset