Note
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Within Session P300#
This example shows how to perform a within session analysis on three different P300 datasets.
We will compare two pipelines :
Riemannian geometry
XDAWN with Linear Discriminant Analysis
We will use the P300 paradigm, which uses the AUC as metric.
# Authors: Pedro Rodrigues <pedro.rodrigues01@gmail.com>
#
# License: BSD (3-clause)
import warnings
import matplotlib.pyplot as plt
import seaborn as sns
from mne.decoding import Vectorizer
from pyriemann.estimation import Xdawn, XdawnCovariances
from pyriemann.tangentspace import TangentSpace
from sklearn.discriminant_analysis import LinearDiscriminantAnalysis as LDA
from sklearn.pipeline import make_pipeline
import moabb
from moabb.datasets import BNCI2014_009
from moabb.evaluations import WithinSessionEvaluation
from moabb.paradigms import P300
getting rid of the warnings about the future
warnings.simplefilter(action="ignore", category=FutureWarning)
warnings.simplefilter(action="ignore", category=RuntimeWarning)
moabb.set_log_level("info")
Create Pipelines#
Pipelines must be a dict of sklearn pipeline transformer.
pipelines = {}
We have to do this because the classes are called ‘Target’ and ‘NonTarget’ but the evaluation function uses a LabelEncoder, transforming them to 0 and 1
labels_dict = {"Target": 1, "NonTarget": 0}
pipelines["RG+LDA"] = make_pipeline(
XdawnCovariances(
nfilter=2, classes=[labels_dict["Target"]], estimator="lwf", xdawn_estimator="scm"
),
TangentSpace(),
LDA(solver="lsqr", shrinkage="auto"),
)
pipelines["Xdw+LDA"] = make_pipeline(
Xdawn(nfilter=2, estimator="scm"), Vectorizer(), LDA(solver="lsqr", shrinkage="auto")
)
Evaluation#
We define the paradigm (P300) and use all three datasets available for it. The evaluation will return a DataFrame containing a single AUC score for each subject / session of the dataset, and for each pipeline.
Results are saved into the database, so that if you add a new pipeline, it will not run again the evaluation unless a parameter has changed. Results can be overwritten if necessary.
paradigm = P300(resample=128)
dataset = BNCI2014_009()
dataset.subject_list = dataset.subject_list[:2]
datasets = [dataset]
overwrite = True # set to True if we want to overwrite cached results
evaluation = WithinSessionEvaluation(
paradigm=paradigm, datasets=datasets, suffix="examples", overwrite=overwrite
)
results = evaluation.process(pipelines)
BNCI2014-009-WithinSession: 0%| | 0/2 [00:00<?, ?it/s]
0%| | 0.00/18.5M [00:00<?, ?B/s]
0%| | 8.19k/18.5M [00:00<04:28, 68.9kB/s]
0%| | 56.3k/18.5M [00:00<01:09, 265kB/s]
1%|▎ | 153k/18.5M [00:00<00:36, 510kB/s]
2%|▋ | 352k/18.5M [00:00<00:18, 964kB/s]
4%|█▌ | 736k/18.5M [00:00<00:10, 1.77MB/s]
8%|███ | 1.51M/18.5M [00:00<00:05, 3.36MB/s]
16%|█████▊ | 2.90M/18.5M [00:00<00:02, 6.04MB/s]
30%|███████████▏ | 5.58M/18.5M [00:00<00:01, 11.2MB/s]
44%|████████████████▏ | 8.10M/18.5M [00:01<00:00, 14.2MB/s]
56%|████████████████████▋ | 10.4M/18.5M [00:01<00:00, 15.6MB/s]
69%|█████████████████████████▍ | 12.7M/18.5M [00:01<00:00, 16.9MB/s]
82%|██████████████████████████████▎ | 15.2M/18.5M [00:01<00:00, 18.0MB/s]
96%|███████████████████████████████████▍ | 17.7M/18.5M [00:01<00:00, 18.9MB/s]
0%| | 0.00/18.5M [00:00<?, ?B/s]
100%|█████████████████████████████████████| 18.5M/18.5M [00:00<00:00, 88.6GB/s]
BNCI2014-009-WithinSession: 50%|█████ | 1/2 [00:10<00:10, 10.32s/it]
0%| | 0.00/18.5M [00:00<?, ?B/s]
0%| | 8.19k/18.5M [00:00<04:29, 68.8kB/s]
0%| | 56.3k/18.5M [00:00<01:09, 264kB/s]
1%|▎ | 153k/18.5M [00:00<00:36, 509kB/s]
2%|▋ | 352k/18.5M [00:00<00:18, 962kB/s]
4%|█▌ | 736k/18.5M [00:00<00:10, 1.77MB/s]
8%|███ | 1.51M/18.5M [00:00<00:05, 3.36MB/s]
16%|██████ | 3.06M/18.5M [00:00<00:02, 6.45MB/s]
30%|██████████▉ | 5.50M/18.5M [00:00<00:01, 10.8MB/s]
42%|███████████████▍ | 7.72M/18.5M [00:01<00:00, 13.1MB/s]
54%|███████████████████▉ | 10.0M/18.5M [00:01<00:00, 14.9MB/s]
66%|████████████████████████▌ | 12.3M/18.5M [00:01<00:00, 16.0MB/s]
78%|████████████████████████████▉ | 14.5M/18.5M [00:01<00:00, 16.7MB/s]
90%|█████████████████████████████████▍ | 16.7M/18.5M [00:01<00:00, 17.1MB/s]
0%| | 0.00/18.5M [00:00<?, ?B/s]
100%|█████████████████████████████████████| 18.5M/18.5M [00:00<00:00, 80.9GB/s]
BNCI2014-009-WithinSession: 100%|██████████| 2/2 [00:20<00:00, 10.18s/it]
BNCI2014-009-WithinSession: 100%|██████████| 2/2 [00:20<00:00, 10.20s/it]
Plot Results#
Here we plot the results to compare the two pipelines
fig, ax = plt.subplots(facecolor="white", figsize=[8, 4])
sns.stripplot(
data=results,
y="score",
x="pipeline",
ax=ax,
jitter=True,
alpha=0.5,
zorder=1,
palette="Set1",
)
sns.pointplot(data=results, y="score", x="pipeline", ax=ax, palette="Set1")
ax.set_ylabel("ROC AUC")
ax.set_ylim(0.5, 1)
plt.show()

Total running time of the script: (0 minutes 22.859 seconds)
Estimated memory usage: 402 MB