# \#covariance **URL:** https://mne.discourse.group/tag/covariance/105.md [Latest](https://mne.discourse.group/latest.md) · [Categories](https://mne.discourse.group/categories.md) · [Tags](https://mne.discourse.group/tags.md) --- ## [Covariance matrices for LCMV: normalization, regularization etc](https://mne.discourse.group/t/covariance-matrices-for-lcmv-normalization-regularization-etc/11588)
**Author:** [@l\_p\_cat](https://mne.discourse.group/u/l_p_cat)\ **Replies:** 0\ **Last updated:** [November 23, 2025, 7:29pm UTC](https://mne.discourse.group/t/covariance-matrices-for-lcmv-normalization-regularization-etc/11588 "2025-11-23T19:29:36Z")
Hello everyone, I’m getting used to the LCMV beamformer source-localisation method and I’m a bit confused about operations involving covariance matrices. I’m using this tutorial as a reference, but some points are still… --- ## [Understanding changes in source reconstruction based on the data used for covariance](https://mne.discourse.group/t/understanding-changes-in-source-reconstruction-based-on-the-data-used-for-covariance/11505)
**Author:** [@SilvanaHuertas](https://mne.discourse.group/u/SilvanaHuertas)\ **Replies:** 0\ **Last updated:** [September 22, 2025, 11:44am UTC](https://mne.discourse.group/t/understanding-changes-in-source-reconstruction-based-on-the-data-used-for-covariance/11505 "2025-09-22T11:44:18Z")
Hi everyone, I’m performing source reconstruction on my EEG data (eLORETA), but I’ve noticed that the results vary considerably depending on how I calculate the covariance from baseline data. I’m struggling to decide wh… --- ## [How choose parameters of compute\_covariance and make\_inverse\_operator for EEG source localization?](https://mne.discourse.group/t/how-choose-parameters-of-compute-covariance-and-make-inverse-operator-for-eeg-source-localization/10619)
**Author:** [@FannyGrosselin](https://mne.discourse.group/u/FannyGrosselin)\ **Replies:** 5\ **Last updated:** [December 12, 2024, 1:06pm UTC](https://mne.discourse.group/t/how-choose-parameters-of-compute-covariance-and-make-inverse-operator-for-eeg-source-localization/10619 "2024-12-12T13:06:51Z")
MNE version: 1.7.1 operating system: Windows 10 Dear MNE community, I am novice in source localization and I am not completely sure about how choose good parameters of some functions I used to do source localization o… --- ## [Unfiltered noise covariance matrix](https://mne.discourse.group/t/unfiltered-noise-covariance-matrix/8300)
**Author:** [@Rauf](https://mne.discourse.group/u/Rauf)\ **Replies:** 1\ **Last updated:** [February 8, 2024, 5:34pm UTC](https://mne.discourse.group/t/unfiltered-noise-covariance-matrix/8300 "2024-02-08T17:34:20Z")
Hi I am using noise covariance matrix that was calculated from the resting state data in order to compute the inverse solution and is not filtered at all. However, my data is currently filtered between 1 and 30 Hz. My q… --- ## [Scale difference between sensors (mag, grad, eeg) after whitening epoched data](https://mne.discourse.group/t/scale-difference-between-sensors-mag-grad-eeg-after-whitening-epoched-data/8157)
**Author:** [@allermat](https://mne.discourse.group/u/allermat)\ **Replies:** 9\ **Last updated:** [January 24, 2024, 10:04am UTC](https://mne.discourse.group/t/scale-difference-between-sensors-mag-grad-eeg-after-whitening-epoched-data/8157 "2024-01-24T10:04:16Z")
Hi, EDIT: I clarified some details below and added system info at the end I am running RSA analysis on MEG data combined across sensors (MAG, GRAD and EEG). I tried to whiten the epoched data before applying RSA and I … --- ## [noise covariance explanantion](https://mne.discourse.group/t/noise-covariance-explanantion/8110)
**Author:** [@codZeus](https://mne.discourse.group/u/codZeus)\ **Replies:** 4\ **Last updated:** [January 10, 2024, 3:52pm UTC](https://mne.discourse.group/t/noise-covariance-explanantion/8110 "2024-01-10T15:52:54Z")
Hi everyone, I know the data from the sensor will be either under-determined or over-determined.(structure-wise), meaning its an inverse problem. Why do we calculate the noise covariance? Conceptually I know source lo… --- ## [error using mne.compute\_covariance and evoked response](https://mne.discourse.group/t/error-using-mne-compute-covariance-and-evoked-response/8093)
**Author:** [@codZeus](https://mne.discourse.group/u/codZeus)\ **Replies:** 7\ **Last updated:** [January 8, 2024, 6:50pm UTC](https://mne.discourse.group/t/error-using-mne-compute-covariance-and-evoked-response/8093 "2024-01-08T18:50:21Z")
Hi, A follow up question to my previous one. I want to compute the covariance using mne.compute\_covariance using the code snippets below import numpy as np import mne import os.path as op from mne.datasets import eegbc…