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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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Clinical Significance of Mittens

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Dr. Rishabh Pathak

The clinical significance of mittens in EEG recordings has evolved over time. Here are the key points regarding their clinical relevance:

1. Normal Variants

    • Current Understanding: Mittens are now considered normal variants in EEG patterns, particularly in adults. They are typically benign and do not indicate any underlying pathology when observed in the context of normal sleep.

2. Historical Context

    • Previous Associations: Historically, mittens were believed to be markers of various neurological and psychiatric conditions, including thalamic tumors, epilepsy, parkinsonism, eating disorders, mood disorders, and psychosis. Early EEG research suggested correlations between the morphology of the mitten pattern and these conditions.

3. Misinterpretation Risks

    • Potential for Misdiagnosis: There is a risk of misinterpreting the mitten pattern as epileptiform activity, which could lead to incorrect diagnoses. This highlights the importance of distinguishing mittens from pathological findings such as interictal epileptiform discharges (IEDs).

4. Research Limitations

    • Methodological Concerns: The earlier associations of mittens with various clinical conditions may have been influenced by methodological issues in research, such as small sample sizes, lack of control groups, and changes in diagnostic criteria over time. Modern approaches have not replicated these interpretations, reinforcing the view of mittens as benign.

5. Recognition and Distinction

    • Importance in Clinical Practice: The primary clinical significance of mittens today lies in their recognition and the ability to distinguish them from epileptiform abnormalities. Accurate identification helps prevent misdiagnosis and ensures appropriate clinical management.

Summary

Mittens are now recognized as normal EEG variants, primarily associated with NREM sleep. While they were once thought to indicate various neurological and psychiatric disorders, current understanding emphasizes their benign nature and the importance of distinguishing them from pathological patterns to avoid misdiagnosis.

 

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