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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 first step in brain development: Differentiation of the neural Progenitor Cells

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Dr. Rishabh Pathak


The differentiation of neural progenitor cells marks a critical early step in brain development. Here are some key points regarding this process:


1.     Neural Progenitor Cells:

o    Neural progenitor cells are a mitotic population of cells that have the capacity to divide and give rise to different types of neural cells, including neurons and glial cells.

o    These cells play a crucial role in generating the diverse cell types that populate the developing brain and contribute to the formation of neural circuits.

o    Neural progenitor cells are derived from neuroectodermal stem cells and undergo complex cascades of molecular signaling to differentiate into specific neural cell types.

2.     Differentiation Process:

o    The differentiation of neural progenitor cells involves a series of molecular signaling events that regulate their fate and specialization.

o    During gastrulation, specific populations of cells differentiate into neural progenitor cells along the rostral-caudal midline of the embryo, guided by complex genetic interactions.

o    The differentiation of neural progenitor cells is influenced by multiple gene products and signaling pathways that orchestrate their development into mature neural cell types.

3.     Role in Brain Maturation:

o    The differentiation of neural progenitor cells is essential for the generation of neurons, which form the basis of neural circuits and networks in the developing brain.

o    This process contributes to the expansion of the neuronal population and the establishment of the structural framework of the brain during early development.

o    Genetic patterning and neurogenesis interact with the differentiation of neural progenitor cells to shape the maturation of the brain and establish its functional organization.

In summary, the differentiation of neural progenitor cells represents a crucial early step in brain development, laying the foundation for the generation of diverse neural cell types and the establishment of neural circuits essential for brain maturation and function.

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