Questions about the statistical process of sampling from a population, in order to obtain information for use in statistical learning, estimation, hypothesis testing about some population or process. Use this tag along with the tags (probability), (probability-theory) or (statistics).
Questions tagged [sampling]
1377 questions
0
votes
0 answers
Probability of a sample mean
I am working on the following problem:
The Department of Environmental Protection demands that your power plant show a mean NOx emission less than 5lb/MWh. Your plant's daily NOx emission fluctuates randomly with a mean of 4.9lb/MWh and a standard…
mXdX
- 571
- 3
- 14
0
votes
0 answers
Finding the most typical individual in a mutivariate population
I have data for a large number of unique populations. In each population each individual is described by a number of categorical and numeric variables. I want to conduct an analysis on each population, and taking into account the descriptive…
Terry B
- 1
0
votes
0 answers
Optimum sampling strategy for unknown function
this question is derived from a technical context (which I'll describe below so you get where this is aimed), but I think it's more of a math probelm: Assume you want to measure a sensor output which can have values from say 0 to 100 (we measure…
jjstcool
- 252
0
votes
1 answer
Random numbers and sampling from uniform distrubution
U1 ~ Uniform[0,1] and U2 ~ Uniform[2, 3]. In which region of the U1-U2 plane is the joint pdf of U1,U2 nonzero?
I have not understood the meaning of U1-U2 plane here.. Can anyone please explain how do I go about solving this question?
Harshada Kelkar
- 103
0
votes
1 answer
How to sample from joint Bernoulli distribution?
I have done searches on google.com and here but haven't found a related one. I apologize if this is a re-post.
Here is my question:
I have a set $n$ of Bernoulli random numbers, and I know the marginal distributions $p_i$ and pairwise joint…
Feng
- 1
0
votes
1 answer
Uniformly sample subboxes from a box
Given a box anchored at $(0, 0)$ and width $w$ and height $h$, I want to randomly select a subbox anchored at $(0, 0)$ with height $w'$ and width $h'$ such that the area of this subbox is a threshold $\alpha \in (0,1]$ times the area of the original…
JT_NL
- 14,514
0
votes
1 answer
What is the name of (1-a)*current + a*sample
Say we take a sample every time unit, we have a calibrated value which needs tracking for drift, however every sample has a given variance causing jumping if we were to use it directly as the new calibrated value, therefore we use…
wich
- 128
- 4
0
votes
1 answer
Sampling and aliasing of a signal
I'm given the signal $x(t)=\cos(100*\pi*t)+\cos(200*\pi*t)+\sin(500*\pi*t)$
and I need to find the least sampling frequency in order to reconstruct the $x(t)$ signal from the following of it's samples.
Any thoughts?
0
votes
1 answer
sampling technique: lower error in estimation on using higher sampling rate
I am using sampling to estimate characteristics of a population. My sampling ratio is 32. I take N/32 samples, calculate their sum and multiply by 32. Then I compare it to actual value to get error. It is 3.67%.
Then I take sampling ratio as 64 and…
user984260
- 105
0
votes
1 answer
Generating Random Variates from CDF
Suppose I am given a CDF of a distribution, given by $F(x) \propto x + x^2 + x^4 + x^7$. How do I generate a random variable from this distribution?
Dwaipayan Gupta
- 285