Getting Started
Installation
Using pip, you can install adopy from PyPI.
pip install adopy
Instead, you can install the developmental version in the GitHub repository.
pip install git+https://github.com/adopy/adopy.git@develop
Quick-start guide
Here, we present how to use ADOpy to compute optimal designs for an experiment. Assuming an arbitrary task and a model, this section shows how users can apply the Adaptive Design Optimization procedure into their own tasks and models from the start.

A simple diagram for the Adaptive Design Optimization.
Step 1. Define a task using adopy.Task
Assume that a user want to use ADOpy for an arbitrary task with two design
variables (x1
and x2
) where participants can make a binary choice
(choice
) on each trial. Then, the task can be defined with
adopy.Task
as described below:
from adopy import Task
task = Task(name='My New Experiment', # Name of the task (optional)
designs = ['x1', 'x2'], # Labels of design variables
responses = ['choice']) # Labels of response variables
Step 2. Define a model using adopy.Model
To predict partipants’ choices, here we assume a logistic regression model
that calculates the probability to make a positive response using three model
parameters (b0
, b1
, and b2
):
Then, users should define a function to compute the log likelihood of a certain choice based on design variables and model parameters:
import numpy as np
from scipy.stats import bernoulli
def calculate_loglik(x1, x2, b0, b1, b2, choice):
"""A function to compute the probability of a positive response."""
logit = b0 + x1 * b1 + x1 * b2
p_obs = 1. / (1 + np.exp(-logit))
return bernoulli.logpmf(choice, p_obs)
Using the information and the function, the model can be defined with
adopy.Model
:
from adopy import Model
model = Model(name='My Logistic Model', # Name of the model (optional)
params=['b0', 'b1', 'b2'], # Labels of model parameters
func=calculate_loglik) # A log likelihood function
Step 3. Define grids for design variables, model parameters, and response variables
Since ADOpy uses grid search to search the design space and parameter space, you must define a grid for design variables, model parameters, and response variables. The grid object can be defined as a Python dictionary. Labels used on the Task and Model class above should be set as its keys, and the corresponding grid points should be set as its values.
import numpy as np
grid_designs = {
'x1': np.linspace(0, 50, 100), # 100 grid points within [0, 50]
'x2': np.linspace(-20, 30, 100), # 100 grid points within [-20, 30]
}
grid_param = {
'b0': np.linspace(-5, 5, 100), # 100 grid points within [-5, 5]
'b1': np.linspace(-5, 5, 100), # 100 grid points within [-5, 5]
'b2': np.linspace(-5, 5, 100), # 100 grid points within [-5, 5]
}
grid_response = {
'choice': [0, 1] # Binary choice
}
Step 4. Initialize an engine using adopy.Engine
Using the objects created so far, an engine should be initialized using
adopy.Engine
. It contains built-in functions to compute an
optimal design using ADO.
from adopy import Engine
engine = Engine(model=model, # Model object
task=task, # Task object
grid_design=grid_design, # grid for design variables
grid_param=grid_param, # grid for model parameters
grid_response=grid_response) # grid for response variables
Step 5. Compute a design using the engine
# Compute an optimal design based on the ADO
design = engine.get_design()
design = engine.get_design('optimal')
# Compute a randomly chosen design, as is typically done in non-ADO experiments
design = engine.get_design('random')
Step 6. Collect an observation in your experiment
# Get a response from a participant using your own code
response = ...
Step 7. Update the engine with the observation
# Update the engine with the design and the corresponding response
engine.update(design, response)
Step 8. Repeat Step 5 through Step 7 until the experiment is over
NUM_TRIAL = 100 # number of trials
for trial in range(NUM_TRIAL):
# Compute an optimal design for the current trial
design = engine.get_design('optimal')
# Get a response using the optimal design
response = ... # Using users' own codes
# Update the engine
engine.update(design, response)