Mathematics Stack Exchange
Mathematics Stack Exchange

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.

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. Mathematical models are used not only in the natural sciences (such as physics, biology, earth science, meteorology) and engineering disciplines (e.g. computer science, artificial intelligence), but also in the social sciences (such as economics, psychology, sociology and political science); physicists, engineers, statisticians, operations research analysts and economists use mathematical models most extensively. A model may help to explain a system and to study the effects of different components, and to make predictions about behaviour.

2372 questions
0
votes
2 answers

Is it possible to write sin x as a result of its derivative?

Basically, I'd like to model sin x, but make it's derivative tend towards 0, so as x increases, it becomes a constant y = 0. The function begins like a typical sin x function, but slowly the fluctuation decreases until it isn't there anymore. If…
shintuku
  • 61
0
votes
1 answer

Population model approximation

The model we are using is $\frac{dp}{dt} = KP(P-M)$. Determine when P=75. Given a table of years and the populations during those years. Specifically focusing on $1925$ and $1975$ with an h value of 1. Where the respective populations are $25$ and…
K. Gibson
  • 2,381
0
votes
0 answers

Formulate a model that predicts the amount of oil in the gulf on day n.

I believe I have the mathematical model correct. My main concern is part d. I am unsure of how to even approach this. Do I need to first calculate how much oil is cleaned after 25 days with my math model from part a? Then, how do I include the 100…
Advent21
  • 55
0
votes
0 answers

I need a transfer function for salt water balance control mechanism in human kidney to run on a matlab.

I want to model the control system mechanism of salt water balance in human kidney with the transfer function technique. But I am having problem finding the transfer function from the mathematical transport equations.
Pramod
  • 1
  • 1
  • 1
  • 3
0
votes
0 answers

Modeling the rate of change of choosing probability for a group

Suppose $x\in[0,1]$ and $1-x$ are weight factors (or say choosing probabilities) of two groups $G_1$ and $G_2$.The rate of change of $x$ is proportional to the payoff difference of the two groups, say $P=\pi(G_1)-\pi(G_2)\in[-1,1]$. I tried with…
Rajib
  • 11
0
votes
0 answers

How would one go about creating a mathematical model following this spec?

A motor insurance company that provides policies covering the costs of car repair resulting from road accidents would like you to build a mathematical model for estimating the probability that the total size of all claims from such policies in 2020…
user732117
0
votes
0 answers

Transfer function identification without response test

I've been using a doublet test to generate data, and then I fitted a first-order linear system with a time delay to determine the transfer function of a system. With that, I tuned a PID controller. However, turns out, in the real scenario,…
cheesus
  • 149
0
votes
1 answer

Looking for the correct terminology for this type of problem

I have a sequence of real valued tuples $(x_1,y_1),...,(x_k,y_k)$ and I am looking for ideas of modelling a function $f$ such that the error $f(x_i)-y_i$ is small. Is there a theory for this type of problem? How do I decide what type of function to…
Leevi L
  • 101
  • 3
0
votes
1 answer

Notation for set of sequences from another set that have a unique variable.

I have difficulty wrapping my head around how to write such notation. Here's my data: $j = 2$ $k = 10$ $X$ - combination, sequence of digits, ex: $(1, 2, 5)$ $Sx$ - sum of digits inside sequence $X$ $C$ - set of all combinations $X$, where $|X| \in…
JTinkers
  • 149
0
votes
2 answers

Logistic growth model

Find the solution of the model when $y(0)=100$ $\frac{dy}{dt}=2y(y-1)(3-y)$ This is what I have using partial fractions we get $1=A(y-1)(3-y)+B(2y)(3-y)+C(2y)(y-1)$ We then get that : $A=\frac{-1}{3}, B=\frac{1}{4}, C=\frac{1}{12}$. Then I have…
Killercamin
  • 801
  • 4
  • 17
  • 39
0
votes
1 answer

Hankel norm and H infinity norm model reduction exam question.

Shown below is a question from a model reduction exam. I'm not sure how to answer the questions and I'm wondering if my approach is correct. A continuous time system relates the inputs $u_1$ and $u_2$ to the output $y$ according to the differential…
user463102
  • 449
0
votes
1 answer

How to know how many points I need to fit a model?

I need to do viscosity measurements at different temperatures in order to fit a model of the form (Flucher equation): $$\log_{10}{\eta}=A+\frac{B}{T-T_0}$$ Where $T_0$ is constant and known, $T$ is the temperature at which I'm making the…
corcholatacolormarengo
  • 111
0
votes
0 answers

I need to get mathematical model for such matrices

I have a question similar to another question I've asked here, but it's with more parameters. The question is, need to find the mathematical model for the relationship between number of columns and all possible number of combinations when…
Zeyad_Zeyad
  • 146
0
votes
1 answer

how to estimate a variable's upper limit with 95% confidence level?

Suppose I have a variable, $S(t)$, for stock price. So always have $S(t) > 0$. $S(t)$ is a random variable, with some volatility $\sigma$ and trend. Now the requirement is to estimate $\hat S(t+1)$ with at 95% confidence level, or: estimate $\hat…
athos
  • 5,177
0
votes
1 answer

Predicting future values or modeling data

Suppose I know that this relationship exists y=(xb-b)+c+d if I had a table of y values for different values of x,b,c and d and I didnt know this relationship how would I go about finding this relationship. Would regression analysis produce the…
Tariro Manyika
  • 111
1 2 3
…
11 12