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## myregrinv

version 2.0.0.0 (15.2 KB) by Giuseppe Cardillo

### Giuseppe Cardillo (view profile)

Resolve a calibration problem that is: to estimate mean value and confidence interval of x since y

Updated 05 Apr 2018

Resolve a calibration problem (inverse regression problem) that is: to estimate mean value and confidence interval of x since y. This function computes a least-square linear regression using the supplied calibration points and then computes the X values for a supplied y observed vector. This routine uses MYREGR function. If it is not present on the computer, myregrinv will try to download it from FEX References: Sokal R.R. and Rohlf F.J. 2003 BIOMETRY. The Principles and Practice of Statistics in Biological Research (3rd ed., 8th printing, Freeman and Company, New York, XIX + 887 p.) pag. 491 - 493.

Created by Giuseppe Cardillo
giuseppe.cardillo-edta@poste.it

To cite this file, this would be an appropriate format: Cardillo G. (2007) MyRegressionINV: resolve a calibration problem that is: to estimate mean value and confidence interval of x since y. http://www.mathworks.com/matlabcentral/fileexchange/15952

### Cite As

Giuseppe Cardillo (2020). myregrinv (https://www.github.com/dnafinder/myregrinv), GitHub. Retrieved .

Giuseppe Cardillo

A calibration problem (inverse regression problem) is: to estimate mean value and confidence interval of x since y.
I used university lessons issues and the indicated reference is:
Sokal R.R. and Rohlf F.J. 2003 BIOMETRY. The Principles and Practice of Statistics in Biological Research (3rd ed., 8th printing, Freeman and Company, New York, XIX + 887 p.) pag. 491 - 493.

For the confidence intervals (CIs) first of all you must check if these CIs exist (in the new upload version this is implemented). Then you must calculate a parameter K. K is a value depending from alpha and degrees of freedom of error variance; it can be estimated by tinv(alpha/2,n-2), the same used in MYREGR function to test slope and intercept.

Dimitri Shvorob

What is the 'calibration problem'? Can you provide a reference? I am especially interested in how you construct CIs.