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Uncertainty in Multiclass Classification

Dr. Rishabh Pathak
1. What is Uncertainty in Classification? Uncertainty refers to the model’s confidence or doubt in its predictions. Quantifying uncertainty is important to understand how reliable each prediction is. In multiclass classification , uncertainty estimates provide probabilities over multiple classes, reflecting how sure the model is about each possible class. 2. Methods to Estimate Uncertainty in Multiclass Classification Most multiclass classifiers provide methods such as: predict_proba: Returns a probability distribution across all classes. decision_function: Returns scores or margins for each class (sometimes called raw or uncalibrated confidence scores). The probability distribution from predict_proba captures the uncertainty by assigning a probability to each class. 3. Shape and Interpretation of predict_proba in Multiclass Output shape: (n_samples, n_classes) Each row corresponds to the probabilities of ...
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Co-occurring waves of Paroxysmal Fast Activity

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Dr. Rishabh Pathak

Co-occurring waves with Paroxysmal Fast Activity (PFA) are important for understanding the context in which PFA occurs and its clinical significance. 

1. Background Activity

    • PFA typically occurs in EEGs that exhibit at least mildly abnormal background activity. More commonly, the background may show moderately abnormal slowing, which can be indicative of underlying neurological conditions.

2. Other Epileptiform Abnormalities

    • PFA often co-occurs with other types of interictal epileptiform discharges (IEDs), such as spikes, sharps, or complexes of either a spike or a sharp followed by an after-going slow wave. These additional abnormalities may appear immediately following PFA.

3. Multifocal Independent Spike Discharges (MISD)

    • The presence of PFA is frequently associated with multifocal independent spike discharges (MISD). This means that the EEG may show multiple localizations of spikes that are independent of each other, which can complicate the interpretation of the EEG and provide insights into the patient's seizure activity.

4. Ictal Context

    • In some cases, PFA may be observed in the context of seizures, particularly generalized-onset seizures. When PFA is associated with seizures, it may be accompanied by very fast activity related to seizure-related muscle artifact, which can further complicate the EEG interpretation.

Summary

In summary, Paroxysmal Fast Activity (PFA) is often seen alongside abnormal background activity and other interictal epileptiform discharges, such as spikes and sharps. The presence of multifocal independent spike discharges (MISD) and the potential for PFA to occur in ictal contexts are also significant. Recognizing these co-occurring waves is essential for accurate EEG interpretation and understanding the clinical implications of PFA in patients with epilepsy or other neurological disorders.

 

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