add additional test functions and psychophysics task and dataset from Letham et al. 2022 (#350)

Summary:

Additional high-dimensional test functions and real psychophysics task are added to problem.py for benchmarking performance of acquistions functions or GP models. The code and dataset are obtained from https://github.com/facebookresearch/bernoulli_lse/blob/main/problems.py.

Differential Revision: D57885175

Author: wenx-guo

aepsych/benchmark/problem.py

@@ -4,16 +4,23 @@
 
 # This source code is licensed under the license found in the
 # LICENSE file in the root directory of this source tree.
-
+import os
 from functools import cached_property
 from typing import Any, Dict, Union
 
 import aepsych
 import numpy as np
 import torch
+from scipy.stats import bernoulli, norm, pearsonr
 from aepsych.strategy import SequentialStrategy, Strategy
 from aepsych.utils import make_scaled_sobol
-from scipy.stats import bernoulli, norm, pearsonr
+from aepsych.benchmark.test_functions import (
+    modified_hartmann6,
+    discrim_highdim,
+    novel_discrimination_testfun,
+)
+from aepsych.models import GPClassificationModel
+
 
 
 class Problem:
@@ -281,3 +288,122 @@ def evaluate(self, strat: Union[Strategy, SequentialStrategy]) -> Dict[str, floa
         )
 
         return metrics
+
+"""
+The LSEProblemWithEdgeLogging, DiscrimLowDim, DiscrimHighDim, ContrastSensitivity6d, and Hartmann6Binary classes
+are copied from bernoulli_lse repository (https://github.com/facebookresearch/bernoulli_lse) by Letham et al. 2022.
+"""
+class LSEProblemWithEdgeLogging(LSEProblem):
+    eps = 0.05
+
+    def evaluate(self, strat):
+        metrics = super().evaluate(strat)
+
+        # add number of edge samples to the log
+
+        # get the trials selected by the final strat only
+        n_opt_trials = strat.strat_list[-1].n_trials
+
+        lb, ub = strat.lb, strat.ub
+        r = ub - lb
+        lb2 = lb + self.eps * r
+        ub2 = ub - self.eps * r
+
+        near_edge = (
+            np.logical_or(
+                (strat.x[-n_opt_trials:, :] <= lb2), (strat.x[-n_opt_trials:, :] >= ub2)
+            )
+            .any(axis=-1)
+            .double()
+        )
+
+        metrics["prop_edge_sampling_mean"] = near_edge.mean().item()
+        metrics["prop_edge_sampling_err"] = (
+            2 * near_edge.std() / np.sqrt(len(near_edge))
+        ).item()
+        return metrics
+
+
+class DiscrimLowDim(LSEProblemWithEdgeLogging):
+    name = "discrim_lowdim"
+    bounds = torch.tensor([[-1, 1], [-1, 1]], dtype=torch.double).T
+    threshold = 0.75
+
+    def f(self, x: torch.Tensor) -> torch.Tensor:
+        return torch.tensor(novel_discrimination_testfun(x), dtype=torch.double)
+
+
+class DiscrimHighDim(LSEProblemWithEdgeLogging):
+    name = "discrim_highdim"
+    threshold = 0.75
+    bounds = torch.tensor(
+        [
+            [-1, 1],
+            [-1, 1],
+            [0.5, 1.5],
+            [0.05, 0.15],
+            [0.05, 0.2],
+            [0, 0.9],
+            [0, 3.14 / 2],
+            [0.5, 2],
+        ],
+        dtype=torch.double,
+    ).T
+
+    def f(self, x: torch.Tensor) -> torch.Tensor:
+        return torch.tensor(discrim_highdim(x), dtype=torch.double)
+
+
+class Hartmann6Binary(LSEProblemWithEdgeLogging):
+    name = "hartmann6_binary"
+    threshold = 0.5
+    bounds = torch.stack(
+        (
+            torch.zeros(6, dtype=torch.double),
+            torch.ones(6, dtype=torch.double),
+        )
+    )
+
+    def f(self, X: torch.Tensor) -> torch.Tensor:
+        y = torch.tensor([modified_hartmann6(x) for x in X], dtype=torch.double)
+
+
+class ContrastSensitivity6d(LSEProblemWithEdgeLogging):
+    """
+    Uses a surrogate model fit to real data from a constrast sensitivity study.
+    """
+
+    name = "contrast_sensitivity_6d"
+    threshold = 0.75
+    bounds = torch.tensor(
+        [[-1.5, 0], [-1.5, 0], [0, 20], [0.5, 7], [1, 10], [0, 10]],
+        dtype=torch.double,
+    ).T
+
+    def __init__(self):
+
+        # Load the data
+        self.data = np.loadtxt(
+            os.path.join("..", "..", "dataset", "csf_dataset.csv"),
+            delimiter=",",
+            skiprows=1,
+        )
+        y = torch.LongTensor(self.data[:, 0])
+        x = torch.Tensor(self.data[:, 1:])
+
+        # Fit a model, with a large number of inducing points
+        self.m = GPClassificationModel(
+            lb=self.bounds[0],
+            ub=self.bounds[1],
+            inducing_size=100,
+            inducing_point_method="kmeans++",
+        )
+
+        self.m.fit(
+            x,
+            y,
+        )
+
+    def f(self, X: torch.Tensor) -> torch.Tensor:
+        # clamp f to 0 since we expect p(x) to be lower-bounded at 0.5
+        return torch.clamp(self.m.predict(torch.tensor(X))[0], min=0)