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