No. Unless there are other reasons, the proportion of each stratum that is sampled (the sampling fraction) should all be equal.
That is the correct spelling of "sampling" (taking a sample).
Some factors that might influence the prediction while taking a sample include the size of the sample, the representativeness of the sample compared to the population, the variability within the sample, and the method of sampling used. These factors can impact the accuracy and reliability of the prediction based on the sample.
Data gathered in two different samples in such a way that there is a matching of the first sample data drawn and a corresponding data value in the second sample data. For example, compare two sample means, one for the first exam of the semester and the second for the second exam of the semester, match via the student taking each test.
The main difference in taking the samples is that for a variable sample, measurements of a characteristic of interest are taken, and for an attribute sample, one counts the number of units having or not having specific properties (mostly good/bad or number of flaws). Generally, attribute samples are much larger than variable samples and to be useful, need to be very large, when the proportion of bad units (or flaws) is very small.
A subset of sample space is taking a sample from that sample space.
Yes they can. They can detect lots of other illegal drugs by taking urine samples too.
As the sample size increases, and the number of samples taken increases, the distribution of the means will tend to a normal distribution. This is the Central Limit Theorem (CLT). Try out the applet and you will have a better understanding of the CLT.
yes
Data gathered in two different samples in such a way that there is a matching of the first sample data drawn and a corresponding data value in the second sample data. For example, compare two sample means, one for the first exam of the semester and the second for the second exam of the semester, match via the student taking each test.
Not usually. The testing laboratory gets hundreds of samples per day - they normally only test samples for the specific component the doctor has requested. However - if a sample gives an abnormal result, re-testing might show up other components - which will be reported back to your doctor.
If you count robots taking samples, yes
One popular tool used by biologists to sample ecosystems is the quadrat. A quadrat is a square or rectangular frame that is placed on the ground to sample a specific area. It helps in estimating population density, biodiversity, and distribution of species within an ecosystem.