Drift and diffusion coefficients
Penguin learning project
The project uses 342 complete Palmer penguin records: 240 training-pool and 102 held-out rows. The selected training rows determine feature scaling and model parameters. Source CSV
This project trains weights with softmax, unlike the homepage lab, which uses nearest species averages. Same penguin measurements; different classification methods. Predictions can differ.
PDE and stochastic processes · Describe differential equations and stochastic representations.
PDE and quantum models are not operations on these penguin measurements.
Consider this concept alongside the project; its source assumptions may differ. These observations do not prove a theorem.
Input: 12 × 2; Held-out evaluation: 102 · #58 · 40.6 mm, 193 mm. Known answer: Adélie; Prediction: Adélie · [≈0.7383, ≈0.2444, ≈0.01737].
Used in these source sections: 4.3 Structure from an equation
In the stochastic differential equation, μ is the drift coefficient and σ is the diffusion coefficient.
The coefficients specify deterministic and random changes in the process.
Source formula example
illustration · This is one scalar Euler step with a supplied increment; it does not solve a stochastic differential equation exactly or establish its distribution.
Symbols
- Drift coefficient function.
- Diffusion coefficient function.
- A positive time step.
- A Brownian increment.
Source formula example
This source example uses its own inputs and assumptions. Editing it does not change the project.
Edit a value or the code, then run the example. This is a finite demonstration, not a proof of the paper’s theorem.
This example’s data flow
Code changed. Reset to restore this example’s data flow.
Initial values in code
current=1drift=2diffusion=0.5dt=0.1brownianIncrement=0.2
Calculated here
Result expression: {
current,
drift,
diffusion,
dt,
brownianIncrement,
next: current + drift * dt + diffusion * brownianIncrement,
}
Returns
current- 1
drift- 2
diffusion- 0.5
dt- 0.1
brownianIncrement- 0.2
next- 1.3
Read numbers from input and return the result. JavaScript basics.
Result
Technical statement
The numerical values are invented. This is one scalar Euler step with a supplied increment; it does not solve a stochastic differential equation exactly or establish its distribution.
Source: Inline notation