Acronyms
Biophysical terms and model parameters
AWF	(Intra-) Axonal water fraction
EWF	Extra-axonal water fraction
FVF	Fibre volume fraction
HCFM	Hollow cylinder fibre model
ICVF	Intra-cellular volume fraction (from NODDI)
MWF	Myelin water fraction (Eq. 6)
gratio	g-ratio
Magnetic resonance imaging and sequence acronyms
dMRI	Diffusion-weighted Magnetic Resonance Imaging
DWI	Diffusion-weighting Imaging
GRE	Gradient-recalled echo
meGRE	Multi-echo gradient-recalled echo
OC	Optic chiasm
R2*	Effective transverse relaxation rate
R2,iso*	Orientation independent or isotropic part of R2*
TE	Echo time
TEmax	Maximal echo time
Hollow cylinder fibre model parameters
SA	Signal of the intra-axonal compartment
SE	Signal of the extra-axonal compartment
SM	Signal of the myelin compartment
SN	Sum of the signals of the non-myelinated (SA and SE) compartments
SC	Sum of all the signal compartments (SA, SE and SM)
R2A	Transverse relaxation rate of the intra-axonal compartment
R2E	Transverse relaxation rate of the extra-axonal compartment
R2N	Transverse relaxation rate of the non-myelinated compartments
R2M	Transverse relaxation rate of the myelin compartment
ρA	Proton density of the intra-axonal compartment
ρE	Proton density of the extra-axonal compartment
ρN	Proton density of the non-myelinated compartments
ρN	Proton density of the myelin compartment
VM	Volume fraction of the myelin compartment
Symbols
In silico and ex vivo data descriptors
$\theta \overrightarrow{\mu }$	Angular orientation of the mean fibre bundle
${\theta }_0$	First angular orientation or angular offset
$\overrightarrow{{\mathrm{B}}_0}$	Main magnetic field
κ	Coefficient of dispersion (from Watson Distribution and NODDI)
$\overrightarrow{\mu }$	Vector of the mean fibre bundle
$\overrightarrow{\mathrm{x}}$	Vector of the individual cylinder in the simulated in silico data
${\mathrm{T}}_{\mathrm{Diff},\mathrm{GRE}}$	Transformation matrix from dMRI to GRE images
${\mathrm{T}}_{\mathrm{GRE}:\mathrm{i},1}$	Transformation matrix from GRE images at the i-th angular orientation measurement to the first angular orientation measurement
Model parameters and analysis metrics
α0	Intercept parameter of M1
α1	Slope or linear parameter of M1
β0	Intercept of M2
β1	Slope of linear parameter of M2
β1,nm	β1 ground-truth value without myelin signal contribution (Eq. 3)
β1,m	β1 ground-truth value with myelin signal contribution (Eq. 4)
β2	Quadrature or second order parameter of M2
εm	Relative difference between fitted β1 and predicted β1,nm
εnm	Relative difference between fitted β1 and predicted β1,m
AIC	Akaike Information Criterion
AICc	Akaike Information Criterion corrected
ΔAICc	Difference of Akaike Information Criteria (Equation 13)
wAICc	Weighted Akaike Information Criterion corrected (Eq. 12)
nRMSD	Normalised root-mean-squared deviation (Eq. 9)
ΔRMSD	Normalised root-mean-squared deviation difference (Eq. 10)
M1	Log-linear model (Eq. 2)
M2	Log-quadratic model (Eq. 1)