Amplitude balanced PEF estimation
نویسنده
چکیده
Inverse theory teaches us that the residual, or misfit function, should be weighted by the inverse covariance matrix of the noise. Because the covariance operator is often difficult to estimate, we can approximate it with a diagonal weight that can be more easily computed. This paper investigates the possible choices of weighting functions for the data residual when prediction-error filters are estimated. Examples with 2-D and 3-D field data prove that it is better to weight the residual than to weight the data before starting the inversion.
منابع مشابه
Distribution of peak expiratory flow variability by age, gender and smoking habits in a random population sample aged 20-70 yrs.
Peak expiratory flow (PEF) variability can be considered as an index of bronchial lability. Population studies on PEF variability are few. The purpose of the current paper is to describe the distribution of PEF variability in a random population sample of adults with a wide age range (20-70 yrs), and to assess relationships to age, gender and smoking habits. PEF data were collected in 511 parti...
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