Questions tagged [mathematical-modeling]
A mathematical model is a description of a system using mathematical concepts and language. The process of developing a mathematical model is termed mathematical modelling.
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Exercise in Acoustic Doppler Effect
I am looking for some guidance on the second part of a geometry type problem which I have given working on and described the next parts below (likely with an error). I have given multiple attempts but ...
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I'm working on finding the constant parameter of the Lotka Volterra differential equations. I am using the LINEST function, but my alpha is negative [closed]
My alpha, which stands for the growth factor of the pray without predation, is negative. Is this a valid value, since it indicates that without predation the population will decrease? If not, how can ...
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Parametric leaf profile?
I am trying to look for a nice way of parametrizing a leaf (botanical) profile. First a regular leaf, but I also would like to do an oak. The trivial answer is to use a B-Spline, but for multiple ...
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Is multicollinearity a problem for optimizing the response with respect to inputs?
I have come to learn that while multicollinearity affects the model "stability" and ability to examine individual affects, but does reduce overall model predictive power.
I am interested in ...
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About Fuzzy Logic [closed]
I am reading fuzzy logic and completed basics like fuzzy sets , fuzzy arithmetic , operations and other things. I want to study advanced topics like Interval type 2 Fuzzy sets, ordered fuzzy numbers ...
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4th Order Tensor multiplication Rules for Sparse Regression analysis
I am working on a problem which involves working with stress and deformation tensors of the order 4. I have a set of data at different time steps for 20 cases and each element stress is 3x3 matrix, so ...
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Neglecting higher order terms in a PDE: why?
This is quite non-rigorous question since I don't think there is a clear-cut theorem answering it. I am deriving a PDE from a system which I know in the limit should give a heat equation. The ...
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Expected relative rate of relapse vs onset in a heterogeneous population (frailty effects)
Model.
Consider the following model reflecting dynamics of major depressive disorder (MDD).
Let $x,y,z$ be the expected proportions never, active, and past MDD, as a function of age beyond 10-years ...
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Waggle-Dance Equation 🐝
Once a foraging bee finds food, it returns to the hive and communicates the location of the food source to the colony using the elegant waggle dance.
Bees interpret this dance by combining their ...
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Dynamics of Snail Balls
It looks like the standard equation of motion for a rigid body rolling without slipping down an incline of angle $\theta$ is
$$
a \;=\; \frac{g\sin\theta}{1 + I/(mR^2)},
$$
where $m$ is the mass, $R$ ...
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Probability distribution of number of successes in n trials without replacement and accounting for order
I've been having some problems on how to model a variant of the sampling without replacement problem.
The context is as follows: Imagine a game with a $N = 40$-card deck, where $K = 8$ cards are of ...
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The value of biologically impossible bifurcation analysis in ODE systems from mathematical biology [closed]
I am studying a 3D system of ODEs derived from a biological model (tumor growth). All parameters are defined to be positive, as negative values would lack biological meaning (e.g., negative loss rates ...
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Compactness with graph theory (gerrymandering)
"To deter gerrymandering, many state constitutions require legislative districts to be 'compact.' Yet, the law offers few precise definitions"
See also: https://en.wikipedia.org/wiki/...
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How to derive a dynamic model for a switched system?
I have been solving following problem which originates in the electrical engineering but from my point of view it is basically a mathematical problem.
I have a dc-dc converter which operates as an ...
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How is a probability-independent formula achieved in the Binomial Options Pricing Model?
How is a probability-independent formula achieved in the Binomial Options Pricing Model?
Intro______________
I am self-studying financial math and I found these lectures on Google written by Karl ...
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