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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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What is Mechanics?

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Dr. Rishabh Pathak

Mechanics is a branch of physics that deals with the behavior of physical bodies when subjected to forces or displacements, and the subsequent effects of these bodies on their environment. It is divided into two main subfields:


  1. Classical Mechanics: This branch of mechanics deals with the motion of macroscopic objects at speeds much lower than the speed of light. It is further divided into two subfields:
    • Statics: Statics deals with objects at rest or in a state of constant motion. It involves the study of forces acting on objects in equilibrium.
    • Dynamics: Dynamics deals with the motion of objects under the influence of forces. It includes the study of acceleration, velocity, and displacement of objects.
  2. Quantum Mechanics: Quantum mechanics is a branch of physics that deals with the behavior of very small particles such as atoms and subatomic particles. It describes the wave-particle duality of matter and the probabilistic nature of particle interactions.

In the context of human movement analysis, mechanics plays a crucial role in understanding how forces act on the human body to produce various types of motion, such as walking, running, jumping, and throwing. By applying principles of mechanics, researchers and practitioners can analyze and optimize human performance, prevent injuries, and design effective rehabilitation programs.

Key concepts in mechanics relevant to human movement analysis include:

  • Force: A force is a push or pull that can cause an object to accelerate, change direction, or deform. In human movement, forces generated by muscles, gravity, and external factors play a significant role in determining motion.
  • Torque: Torque, also known as the moment of force, is a measure of the tendency of a force to rotate an object around an axis. In human movement, torque is essential for understanding joint movements and the generation of rotational motion.
  • Kinematics: Kinematics is the branch of mechanics that deals with the motion of objects without considering the forces causing the motion. It involves concepts such as position, velocity, and acceleration.
  • Kinetics: Kinetics is the branch of mechanics that deals with the forces causing motion. It includes the study of how forces interact with the mass and geometry of objects to produce motion.

By applying the principles of mechanics to human movement analysis, researchers and practitioners can gain insights into the biomechanical basis of human motion, optimize athletic performance, and improve the quality of life for individuals through tailored interventions and rehabilitation programs.

 

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