Showing posts with label Bias. Show all posts
Showing posts with label Bias. Show all posts

Wednesday, February 26, 2020

Difference between sampling and nonsampling error

Difference between sampling and non sampling error

Sampling error
sampling gives rise to certain error known as sampling error the error could not be present in a complete enumeration survey the error can be controlled.
Bias

Biased Errors
This error arise from any biased in selection estimation, etc
For example if in place of simple random sampling deliberate sampling has been used in the particular case some wise is introduced in the Richard and hence such error are called biased sampling error.
Unbiased error
These error arises due to to chance difference between the member of population including in the same per and those not included. An error in statics is different between the value of static and that of corresponding parameter.
Causes of Bias
Bias may arise due to
Faculty process of selection
Faculty work during the collection
Faculty method of analysis.
Faculty selection
faculty selection of the sample main give rise to buyers in a number of ways
Deliberate selection of representatives sample
Conscious or unconscious bias in the selection of random sample.
Substitution
Non-response
Bias due to faculty collection of data
Any consistent error in measurement will give rise to buy whether the measurement are are carried out on a simple or on all the units of the population.
Bias in Analysis
in addition to base which arises from faculty process of selection and faculty collections of information, faculty method of analysis may also introduced by.
Avoidance of Bias
If possibility of bias exist fully objective conclusion cannot be drawn. The first essential of any sampling for sensors produce must therefore be the elimination of all sources of bias.
The sampling error usually decreases with increase in sample size and in fact in which situation the decreases is inversely proportional to the square root of the sample size as as can be seen. Sample survey to provide estimates within permissible margin of error instead of a complete enumeration survey as in the letter the F4 and the cost needed will be substantially higher due to the attempt to reduced sampling error  to zero.
Non sampling errors
non sampling error can occur at every stage of planning and execution of census for survey such error can arise due to a number of causes such as defective method of data collection and tabulation faculty definition incomplete coverage of the population for sample etc.




Black-Scholes formula-R

 Black-Scholes formula-R > BlackScholes <- function(TypeFlag = c("c", "p"), S, X, Time, r, b, sigma) { TypeFla...