For questions about estimation and how and when to estimate correctly
Questions tagged [estimation]
1748 questions
0
votes
2 answers
How to calculate a specified frame rate in milliseconds.
I am writing a program which moves a square image 1 pixel to the right every millisecond. The image starts at a x position of -469 and when it is done it ends up at an x position of 11. I want to move the image to the right 60 pixels a second but…
0
votes
0 answers
Optimal estimation using two measurement
Let's say I have 2 measuremnts of the same thing (for example current temperature) and I want to find the MMSE estimator, i.e to minimize the MSE.
the measurements are independent and the noise in each one is gaussian.
the mathematical formation:
$$…
0
votes
0 answers
How to estimate distance interval from measurements?
I want to measure distance with GPS. However, the GPS is not very precise.
I will do my measurements for repetitions X number of foot lengths. I wonder if I can make better estimations of my position by using the knowledge of taking same lengths…
tompak
- 1
0
votes
1 answer
Estimate two variables given set of approximations
I have a set of approximations of the form
known1 ~= 10X + 15YX - known2
where X and Y are unknown constants and known1 and known2 are known but different in every equation. For instance:
60 ~= 10X + 15YX - 40
50 ~= 10X + 15YX - 30
10 ~= 10X + 15YX…
JonathanR
- 103
0
votes
3 answers
Incalculable Symbol
My nephew recently received this as a piece of homework (he is seven):
"How many grains of sand are there in the world?"
Obviously he Googled the question and it came back with "It is incalculable". Knowing that I'm `into' maths, he asked me if…
GerrySmith
- 309
0
votes
1 answer
How to estimate a simple sum on a calculator paper?
The Government has decided to change the GCSE System by adding a 3rd calculator paper and introducing a grading system of $9-1$ ($9$ for those A** kids given to the top $2.5%$ of the country).
I am currently doing some practice questions on this 3rd…
itshanks
- 532
0
votes
1 answer
What is the expected value of $X^2$ when $X\backsim \frac{n+1}{n}Y$ and $Y\backsim f(y\mid \theta )=\frac{n}{\theta}(\frac y \theta)^{n-1}$
Here's the question again: what is the expected value of $Z^2$ when $Z\backsim \frac{n+1}{n}Y$ and $\displaystyle Y\backsim f(y\mid\theta )=\frac{n}{\theta}\left(\frac y \theta \right)^{n-1}$ from $0$ to $\theta$
I know the set up of the problem is…
David Kang
- 35
0
votes
0 answers
Estimating the optimal set of values
I really know nothing about this sort of thing so hopefully I can at least articulate what I'm trying to find out.
Let's say there's five qualities that can be represented numerically, and these qualities work in harmony; thus one set of numbers can…
clb
- 313
0
votes
0 answers
Ordinary Least Squares vs other methods
Suppose we have the relation $Y_{i}=\beta_{1}+\beta_{2}X_{i}+u_{i}$ with $X_{i}$ and $Y_{i}$ observed values, $\beta_{1}$ and $\beta_{2}$ the parameters and $u_{i}$ the disturbance term. We want to construct estimators of $\beta_{2}$.
The method of…
Rankyaku
- 1
0
votes
1 answer
Estimation, Upper limits, Lower limits
Two rods of length 2.6 cm and 3.5 cm are measured correct to the nearest 0.2 cm. The two rod are joined together, find the lower and upper limit of the new rod.
I get stuck. HOw to do?
user256670
- 113
- 2
- 8
0
votes
1 answer
Estimating Cable Length on a Reel
I have been searching all areas of the internet to try and find a reliable formula for estimating cable length on a reel,
I'm trying to create a faster and more reliable way to estimate cable to enhance the speed of our Stock Take.
So far I have…
Matthew
- 1
0
votes
1 answer
Estimation method starting with too big and too low values
I not sure to what field exactly this question belongs, but math/statistics seemed closest to me. So here we go:
It is a method of estimating a value that informally goes like this (bear with me). You pick two values. One that is clearly too low and…
zigzag
- 101
- 1
0
votes
0 answers
Big Oh notation problem
Retaining the three terms in the series, estimate the remaining series using "Big Oh" notation with the best integer value possible, as $x\to 0$. The series is
$$\ln (\tan (x)) =\ln(x)+ \frac{x^2}{3} + \frac{7x^4}{90} + \frac{62x^6}{2835}+...,…
Stranqer95
- 29
0
votes
1 answer
Understanding NACA Technical Note 194
I am trying to understand this technical note, specifically problem 1 on page 4.
http://naca.central.cranfield.ac.uk/reports/1924/naca-tn-194.pdf
I am quite happy with everything up to equation 2 on page 5. I don't understand where the figure .39D…
DNN
- 115
0
votes
1 answer
Estimating Cdf of a function of random variable given Cdf of a random variable
I have a random variable $X$, whose c.d.f. is known.
Now I want to estimate the c.d.f of $Y = X \cdot Z$, where the only information I have about $Z$ is that it is a discrete r.v. which takes on three values.
What is the best estimate(in MMSE…
Nischal
- 43