The Nautilus sampler

Neural Network-Boosted Importance Nested Sampling

Name

nautilus

Version

0.4.1

Author(s)

Johannes U. Lange

URL

https://github.com/johannesulf/nautilus

Citation(s)

h, t, t, p, s, :, /, /, a, r, x, i, v, ., o, r, g, /, a, b, s, /, 2, 3, 0, 6, ., 1, 6, 9, 2, 3

Parallelism

parallel

Nautilus is an MIT-licensed pure-Python package for Bayesian posterior and evidence estimation. It utilizes importance sampling and efficient space exploration using neural networks. Compared to traditional MCMC and Nested Sampling codes, it often needs fewer likelihood calls and produces much larger posterior samples. Additionally, nautilus is highly accurate and can produce Bayesian evidence estimates with percent precision.

Installation

pip install nautilus-sampler conda install -c conda-forge nautilus-sampler

Parameters

These parameters can be set in the sampler’s section in the ini parameter file. If no default is specified then the parameter is required. A listing of “(empty)” means a blank string is the default.

Name

Type

Description

Default

n_live

integer

number of live points

1500

n_update

integer

number of additions to the live set before a new bound is created

n_live

enlarge

float

factor by which the volume of ellipsoidal bounds is increased

1.1*n_dim

n_batch

integer

number of likelihood evaluations that are performed at each step

100

random_state

int

random seed, negative values give a random random seed

-1

filepath

string

file used for checkpointing, must have .hdf5 ending

‘None’

resume

bool

if True, resume from previous run stored in filepath

True

f_live

float

live set evidence fraction when exploration phase terminates

0.01

n_shell

int

minimum number of points in each shell

n_batch

n_eff

float

minimum effective sample size

10000.0

discard_exploration

bool

whether to discard points drawn in the exploration phase

False

verbose

bool

If true, print information about sampler progress

False