arrow
Return

Fitting a function to time-dependent ensemble averaged data

delete2018-05-03
delete10
delete
OA
AI
K
Karl Fogelmark
M
Michael A. Lomholt
A
Anders Irbäck
T
Tobias Ambjörnsson *
DOI:10.1038/s41598-018-24983-ydelete
deleteOriginal
deleteShare
deleteSave
View PDF
Abstract

Abstract

En 中文
Time-dependent ensemble averages, i.e., trajectory-based averages of some observable, are of importance in many fields of science. A crucial objective when interpreting such data is to fit these averages (for instance, squared displacements) with a function and extract parameters (such as diffusion constants). A commonly overlooked challenge in such function fitting procedures is that fluctuations around mean values, by construction, exhibit temporal correlations. We show that the only available general purpose function fitting methods, correlated chi-square method and the weighted least squares method (which neglects correlation), fail at either robust parameter estimation or accurate error estimation. We remedy this by deriving a new closed-form error estimation formula for weighted least square fitting. The new formula uses the full covariance matrix, i.e., rigorously includes temporal correlations, but is free of the robustness issues, inherent to the correlated chi-square method. We demonstrate its accuracy in four examples of importance in many fields: Brownian motion, damped harmonic oscillation, fractional Brownian motion and continuous time random walks. We also successfully apply our method, weighted least squares including correlation in error estimation (WLS-ICE), to particle tracking data. The WLS-ICE method is applicable to arbitrary fit functions, and we provide a publically available WLS-ICE software.
Keywords:
PARTICLE TRACKING
ANOMALOUS DIFFUSION
SINGLE MOLECULES
DYNAMICS
TRANSPORT
MOTION
AI Summary

AI Summary

Key information extracted from the uploaded paper, including a brief overview, abstract, background, key highlights, visual analysis, and future outlook.

Journal

Scientific Reports cover
Scientific Reports
IF:
3.9
Papers:
28.2W
Citations:
83.5W

Organization

L
lund university
Scholars:
4.1W
Papers: 3.9W
Citations: 54
U
University of Southern Denmark
Scholars:
2.1W
Papers: 2.0W
Citations: 2.9W
Cited Papers

Cited Papers

errShare
errSave
Extracting intracellular diffusive states and transition rates from single-molecule tracking data
err2013-02-10
err334
PREAI
errPersson, Fredrik; Linden, Martin; Unoson, Cecilia; Elf, Johan
errShare
errSave
errShare
errSave
Single-particle tracking: connecting the dots
err2008-08-01
err130
PREAI
errSaxton, Michael J.
errShare
errSave
Inferring transient particle transport dynamics in live cells
err2015-07-20
err130
errOAAI
errMonnier, Nilah; Barry, Zachary; Park, Hye Yoon; Su, Kuan-Chung; Katz, Zachary; English, Brian P.; Dey, Arkajit; Pan, Keyao; Cheeseman, Iain M.; Singer, Robert H.; Bathe, Mark
errShare
errSave
Transpubic Surgery: A New Approach to Difficult Pelvic Operations
err1973-11-01
err0
PREAI
errPablo Morales; Robert Littmann; Mircea Golimbu
errShare
errSave
researcher View more