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main:calibrationcurve [2017/05/19 14:38]
bshirley
main:calibrationcurve [2019/06/26 16:28] (current)
bshirley
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   * **SVM**\\ The [[main:svmsigma | SVM sigma value]] should match the SVM sigma value of the you wish to use for future dose estimation using this curve. Please view the [[main:svmsigma | sigma value]] page for recommended sigma values to select.   * **SVM**\\ The [[main:svmsigma | SVM sigma value]] should match the SVM sigma value of the you wish to use for future dose estimation using this curve. Please view the [[main:svmsigma | sigma value]] page for recommended sigma values to select.
   * **Applied image selection model**\\ The [[main:imageselectionmodel | image selection model]] selected here should match the image selection model chosen during future dose estimation.   * **Applied image selection model**\\ The [[main:imageselectionmodel | image selection model]] selected here should match the image selection model chosen during future dose estimation.
-  * **Input Response-Dose data to create a curve**\\ At least three samples must be input to the dose-response list. For each sample, both dose and response must be input. To add a new sample click "Import", select the appropriate calibration sample and [[main:svmsigma | SVM Sigma value]], and a new entry will appear the dose-response list. Dose is represented in Gray (Gy) units and is known based on the exposure of the calibration sample. For example, if a calibration sample was exposed to radiation at 2 Gy, 2 should be entered in the dose field. The "Import" functionality automatically retrieves DC/Cell of the sample at the specified SVM Sigma value. If desired, these fields can be entered manually by clicking "Input". Response (DC/Cell) can be found in the console after clicking a [[main:processedsample | processed sample]] in the sample list within the [[main:mainGUI | main GUI]]. DC/Cell values are present for sigma values in the range 0.8 to 1.8. The appropriate DC/Cell value to enter corresponds to the [[main:svmsigma | SVM sigma value]] you have chosen to use. Dose-response entries can be removed by clicking a dose-response row and clicking "Remove". After entering all desired dose-response entries, "Validate" must be clicked before the "OK" button will be enabled. "Validate" ensures the contents of the Dose-Response list are numeric. +  * **Input Response-Dose data to create a curve**\\ At least three samples must be input to the dose-response list. For each sample, both dose and response must be input. To add a new sample click "Import", select the appropriate calibration sample and [[main:svmsigma | SVM Sigma value]], and a new entry will appear the dose-response list. Dose is represented in Gray (Gy) units and is known based on the exposure of the calibration sample. For example, if a calibration sample was exposed to radiation at 2 Gy, 2 should be entered in the dose field. The "Import" functionality automatically retrieves DC/Cell of the sample at the specified SVM Sigma value.\\ \\ Double clicking dose or response fields allows the field to be edited if necessary. For each sample to be edited, double click on the dose or response column, which will select the text to be changed. Anything typed while the field is selected will overwrite what was previously present. This process may be repeated in order to edit fields as necessary.\\ \\ If desired, all fields can be entered manually by clicking "Input". Response (DC/Cell) can be found in the console after clicking a [[main:processedsample | processed sample]] in the sample list within the [[main:mainGUI | main GUI]]. DC/Cell values are present for sigma values in the range 0.8 to 1.8. The appropriate DC/Cell value to enter corresponds to the [[main:svmsigma | SVM sigma value]] you have chosen to use. Dose-response entries can be removed by clicking a dose-response row and clicking "Remove".\\ \\ After entering or importing all desired dose-response entries, "Validate" must be clicked before the "OK" button will be enabled. "Validate" ensures the contents of the Dose-Response list are numeric and are greater than zero. 
   * **Click "OK" and save curve**\\ The curve is now created and has been added to the workspace. If you would like to save the curve for future use after the current session, you can save it now. Alternatively, it can be saved later by clicking the {{file:icon:diskette.png?nolink&20}} icon.   * **Click "OK" and save curve**\\ The curve is now created and has been added to the workspace. If you would like to save the curve for future use after the current session, you can save it now. Alternatively, it can be saved later by clicking the {{file:icon:diskette.png?nolink&20}} icon.
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   * **SVM**\\ In almost all cases, SVM should be left to read "Not Applicable" when creating a curve by manually entering coefficients. As described in the warning above, the [[main:svmsigma | SVM sigma value]] is related to how many dicentric chromosomes are found when a sample is processed. If a curve was previously created independently of ADCI software, SVM is not applicable. An SVM should be selected if you are entering curve coefficients from a curve you have previously created using ADCI software, however note it is more straightforward to simply save a curve generated by ADCI software instead of re-entering coefficients in this manner.   * **SVM**\\ In almost all cases, SVM should be left to read "Not Applicable" when creating a curve by manually entering coefficients. As described in the warning above, the [[main:svmsigma | SVM sigma value]] is related to how many dicentric chromosomes are found when a sample is processed. If a curve was previously created independently of ADCI software, SVM is not applicable. An SVM should be selected if you are entering curve coefficients from a curve you have previously created using ADCI software, however note it is more straightforward to simply save a curve generated by ADCI software instead of re-entering coefficients in this manner.
   * **Curve coefficients (A,B, and C)**\\ Three curve coefficients are defined as: <code>A*Dose^2+B*Dose+C</code> Enter values under the headings "Quadratic Coefficient (A)", "Linear Coefficient (B)", and "Intercept (C)".   * **Curve coefficients (A,B, and C)**\\ Three curve coefficients are defined as: <code>A*Dose^2+B*Dose+C</code> Enter values under the headings "Quadratic Coefficient (A)", "Linear Coefficient (B)", and "Intercept (C)".
 +  * **Covariance Matrix of Coefficients (Optional)**\\ A covariance matrix can optionally be entered here. As values in the covariance matrix are symmetric, repetitive values are populated automatically. The presence of a covariance matrix allows curve confidence intervals to be calculated and allows ADCI to take uncertainty based on this calibration curve into account during dose estimation. Note if a covariance matrix is not supplied, uncertainty based on the Poisson nature of dicentric yield can still be taken into account during dose estimation if requested.   
   * **Valid Range for the Curve**\\ ADCI software will not attempt to accurately report estimated dose of a test sample outside the "Min Dose" and "Max Dose" range. The minimum and maximum physical dose (in Gy) present in calibration data should be entered in "Min Dose" and "Max Dose" fields respectively. If [[main:estimatedose | dose is estimated]] using a test sample with estimated dose outside the Min Dose and Max Dose range, the software will report the test sample has estimated dose > Max Dose or < Min Dose.   * **Valid Range for the Curve**\\ ADCI software will not attempt to accurately report estimated dose of a test sample outside the "Min Dose" and "Max Dose" range. The minimum and maximum physical dose (in Gy) present in calibration data should be entered in "Min Dose" and "Max Dose" fields respectively. If [[main:estimatedose | dose is estimated]] using a test sample with estimated dose outside the Min Dose and Max Dose range, the software will report the test sample has estimated dose > Max Dose or < Min Dose.
   * **Click "OK" and save curve**\\ The curve is now created and has been added to the workspace. If you would like to save the curve for future use after the current session, you can save it now. Alternatively, it can be saved later by clicking the {{file:icon:diskette.png?nolink&20}} icon.   * **Click "OK" and save curve**\\ The curve is now created and has been added to the workspace. If you would like to save the curve for future use after the current session, you can save it now. Alternatively, it can be saved later by clicking the {{file:icon:diskette.png?nolink&20}} icon.
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 The Maximum-Likelihood Method is recommended by IAEA and is the default curve fitting method. Note if the curve fitting method is changed, a new curve must be generated for the setting to take effect. Curves generated in the past will not be updated to the new method. The Maximum-Likelihood Method is recommended by IAEA and is the default curve fitting method. Note if the curve fitting method is changed, a new curve must be generated for the setting to take effect. Curves generated in the past will not be updated to the new method.
 +
 +===== Visualization of curves =====
 +Calibration curves can [[main:plots | plotted]] within the plot display section of the [[main:maingui | main GUI]]. All plots can be magnified to view specific intervals. Instructions on how to do this can be found on the [[main:plots | plots information page]] of this wiki. 
  
 ===== Confidence intervals ===== ===== Confidence intervals =====
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 +
 +===== Curve fitting statistics =====
 +Curve fitting stats can be found in the [[main:console | console]] when a curve is highlighted within the [[main:mainGUI | main GUI]] and are also present in [[main:curvereport | calibration curve reports]]. These statistics can be used to evaluate curve "goodness of fit". Available curve fitting statistics are:
 +
 +  * Chi-square ((https://www.gnu.org/software/gsl/doc/html/randist.html#the-chi-squared-distribution))
 +  * Coefficient of determination ((https://www.gnu.org/software/gsl/doc/html/lls.html#multi-parameter-regression))
 +  * Degrees of freedom ((https://en.wikipedia.org/wiki/Degrees_of_freedom_%28statistics%29))
 +
 +Calibration curve degrees of freedom is: n - 3 where n is the number of calibration samples used the generate the curve.
main/calibrationcurve.1495204680.txt.gz · Last modified: 2017/05/19 14:38 by bshirley