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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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Plasticity

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Dr. Rishabh Pathak

Plasticity refers to the brain's ability to reorganize itself by forming new neural connections throughout life in response to experiences, learning, and environmental stimuli. This adaptive capacity allows the brain to change its structure and function in order to optimize performance, recover from injury, and adapt to new challenges. Plasticity is a fundamental property of the nervous system that underlies learning, memory, and various cognitive processes.


There are two main types of plasticity in the brain:


1. Structural Plasticity: Structural plasticity involves changes in the physical structure of the brain, such as the formation of new synapses (connections between neurons), the growth of dendrites (branch-like extensions of neurons), and the reorganization of neural circuits. Structural changes in the brain occur in response to learning, environmental enrichment, and sensory experiences. For example, practicing a new skill can lead to the formation of new neural connections and the strengthening of existing ones, enhancing the brain's ability to perform that skill.


2.  Functional Plasticity: Functional plasticity refers to changes in the functional organization of the brain, including alterations in neural activity patterns and the recruitment of different brain regions for specific tasks. Functional plasticity allows the brain to adapt its processing strategies in response to changing demands and experiences. For instance, after a brain injury, other areas of the brain may compensate for the damaged region by taking on new functions, demonstrating the brain's ability to reorganize and adapt to maintain cognitive abilities.


Plasticity is most pronounced during critical periods of development, such as early childhood, when the brain is highly malleable and responsive to environmental influences. However, plasticity continues throughout life to a certain extent, allowing for ongoing learning, memory formation, and adaptation to new experiences.


Factors that influence brain plasticity include sensory stimulation, motor activities, social interactions, cognitive challenges, and environmental enrichment. By understanding and harnessing the principles of plasticity, researchers and clinicians can develop interventions to promote healthy brain development, enhance cognitive function, and facilitate recovery from brain injuries or neurological disorders.

 

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