Difference between revisions of "Forest Error Analysis for the Physical Sciences"

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= Chi-Square=
 
= Chi-Square=
 +
 +
==P-value==
  
 
Root fundtion to evaluate meaning of Chi-square
 
Root fundtion to evaluate meaning of Chi-square
  
P-value
+
 
 +
Rather, the p-value is
 +
the probability, under the assumption of a hypothesis H , of obtaining data at least as
 +
incompatible with H as the data actually observed.
 
<pre>
 
<pre>
 
root [3] TMath::Prob(1.31,11)
 
root [3] TMath::Prob(1.31,11)

Revision as of 23:05, 17 September 2009

Class Admin

Forest_ErrorAnalysis_Syllabus

Homework

Homework is due at the beginning of class on the assigned day. If you have a documented excuse for your absence, then you will have 24 hours to hand in the homework after being released by your doctor.

Class Policies

http://wiki.iac.isu.edu/index.php/Forest_Class_Policies

Instructional Objectives

Course Catalog Description
Error Analysis for the Physics Sciences 3 credits. Lecture course with computation requirements. Topics include: Error propagation, Probability Distributions, Least Squares fit, multiple regression, goodnes of fit, covariance and correlations.

Prequisites:Math 360.

Course Description
The course assumes that the student has very limited experience with the UNIX environment and C/C++ programming. Homework problems involve modifying and compiling example programs written in C++.

Systematic and Random Errors

Reporting Uncertainties

Notation

X \pm Y = X(Y)

Statistical Distributions

Binomial

Poisson

Gaussian

Lorentzian

Propagation of Uncertainties

Chi-Square

P-value

Root fundtion to evaluate meaning of Chi-square


Rather, the p-value is the probability, under the assumption of a hypothesis H , of obtaining data at least as incompatible with H as the data actually observed.

root [3] TMath::Prob(1.31,11)

Double_t Prob(Double_t chi2, Int_t ndf)
 Computation of the probability for a certain Chi-squared (chi2)
 and number of degrees of freedom (ndf).

 Calculations are based on the incomplete gamma function P(a,x),
 where a=ndf/2 and x=chi2/2.

 P(a,x) represents the probability that the observed Chi-squared
 for a correct model should be less than the value chi2.

 The returned probability corresponds to 1-P(a,x),
 which denotes the probability that an observed Chi-squared exceeds
 the value chi2 by chance, even for a correct model.

--- NvE 14-nov-1998 UU-SAP Utrecht

References

1.) "Data Reduction and Error Analysis for the Physical Sciences", Philip R. Bevington, ISBN-10: 0079112439, ISBN-13: 9780079112439

CPP programs for Bevington

Bevington programs

2.)An Introduction to Error Analysis, John R. Taylor ISBN 978-0-935702-75-0