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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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The formation of Neural tube: The first brain Structure

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Dr. Rishabh Pathak

The formation of the neural tube represents a significant milestone in early brain development, serving as the foundation for the central nervous system. Here are key points regarding the formation of the neural tube:


1.     Neural Tube Development:

o    The neural tube is the precursor to the brain and spinal cord, forming during the third week of gestation in humans.

o    Neural progenitor cells, located along the rostral-caudal midline of the embryo within the neural plate, play a crucial role in the formation of the neural tube.

o    Initially, two ridges form along the sides of the neural plate, with neural progenitor cells positioned between them.

o    Over several days, these ridges rise, fold inward, and fuse to create a hollow tube structure that will give rise to the central nervous system.

2.     Structural Significance:

o    The neural tube represents the first well-defined brain structure in embryonic development, laying the groundwork for the organization of the central nervous system.

o    As the neural tube forms, it establishes the basic structural framework for the brain and spinal cord, setting the stage for further differentiation and maturation of neural cell types.

o    The closure of the neural tube is a critical event in early brain development, ensuring the proper formation of the central nervous system and the subsequent development of neural circuits.

3.     Role in Brain Maturation:

o    The formation of the neural tube marks a crucial step in early brain development, initiating the process of central nervous system formation and organization.

o    Neural progenitor cells within the neural tube give rise to the diverse cell types that populate the brain and spinal cord, contributing to the complexity and functionality of the developing nervous system.

o    Genetic patterning and molecular signaling pathways regulate the development and closure of the neural tube, highlighting the intricate interplay of genetic and environmental factors in brain maturation.

In summary, the formation of the neural tube serves as the initial brain structure in embryonic development, playing a pivotal role in establishing the central nervous system's structural foundation and paving the way for subsequent stages of brain maturation and neural circuit formation.

 

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