States of infinitely many oscillators with linear interaction terms

Physica ◽  
1967 ◽  
Vol 37 (1) ◽  
pp. 23-31 ◽  
Author(s):  
A.F. Verbeure ◽  
E.J. Verboven
Keyword(s):  
Linear Interaction ◽  
Interaction Terms

scholarly journals Baseline Diastolic Blood Pressure and Cardiovascular Outcomes in SPRINT Participants with Chronic Kidney Disease

Kidney360 ◽  
2020 ◽  
Vol 1 (5) ◽  
pp. 368-375
Author(s):  
Tara I. Chang ◽  
Guo Wei ◽  
Robert Boucher ◽  
Holly Kramer ◽  
Glenn M. Chertow ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cox Regression ◽  
Acute Decompensated Heart Failure ◽  
Decompensated Heart Failure ◽  
Cardiovascular Death ◽  
Linear Interaction ◽  
Coronary Syndrome ◽  
End Point ◽  
Interaction Terms ◽  
Lower Baseline

BackgroundWe sought to determine whether intensive systolic BP (SBP) lowering was harmful in Systolic Blood Pressure Intervention Trial (SPRINT) participants with CKD (eGFR<60 ml/min per 1.73 m2) and lower baseline diastolic BP (DBP).MethodsWe related baseline DBP with the SPRINT primary composite end point (myocardial infarction, acute coronary syndrome, stroke, acute decompensated heart failure, or cardiovascular death) and all-cause death. We examined the effect of intensive SBP lowering on these outcomes across the range of baseline DBPs using Cox regression with treatment by baseline DBP interaction terms.ResultsAmong 2646 SPRINT participants with CKD, lower baseline DBP was associated with a higher adjusted hazard of the primary composite end point and all-cause death. For example, participants with baseline DBP of 61 mm Hg (mean baseline DBP in the lowest tertile) experienced a 37% (95% CI, 7% to 75%) higher hazard of the primary outcome relative to participants with baseline DBP of 75 mm Hg (mean baseline DBP for overall). The benefit of intensive SBP lowering was consistent across a range of baseline DBPs on rates of the primary composite end point (linear interaction P value =0.56) and all-cause death (linear interaction P value =0.20).ConclusionsAmong SPRINT participants with baseline CKD, lower DBP was associated with higher rates of the primary composite end point and all-cause death. However, DBP did not seem to modify the benefit of intensive SBP lowering on the primary composite end point or all-cause death. Our results suggest that lower DBP should not necessarily impede more intensive SBP lowering in patients with mild to moderate CKD.

Nonlinearity, Multicollinearity and the Probability of Type II Error in Detecting Interaction

1998 ◽  
Vol 24 (5) ◽  
pp. 615-622 ◽  
Author(s):  
Yoav Ganzach
Keyword(s):  
Multiple Regression ◽  
Type Ii ◽  
Type Ii Error ◽  
Linear Interaction ◽  
Interaction Terms ◽  
True Model ◽  
The Impact

The paper analyzes the impact of the inclusion of quadratic terms on the probability of type II error in testing for interaction in the pres ence of multicollinearity. The analysis focuses on two situations: (a) when the true model includes only linear and interaction terms; and (b) when the true model includes linear, interaction and quadratic terms. The implications of this analysis on the estimation of interaction in multiple regression are discussed.

Note on Peng's treatment of the divergency difficulties in quantized field theories

1948 ◽  
Vol 44 (2) ◽  
pp. 301-303 ◽  
Author(s):  
B. Touschek
Keyword(s):  
Scalar Meson ◽  
Field Theories ◽  
Β Decay ◽  
Charged Scalar ◽  
Linear Interaction ◽  
Self Energy ◽  
Interaction Terms ◽  
Quantized Field ◽  
Physical Reasons ◽  
Scalar Meson Field

The purpose of this note is to show that Peng's (1) method of approximation is not practicable in the case of quadrilinear interaction (i.e. Fermi's (2) original theory of β-decay), and that it does not remove the infinite self-energy of a nucleon in interaction with a charged scalar meson field. The two examples do not, however, provide a serious argument against Peng's theory, since both refer to field theories which have been abandoned for physical reasons. The principal failure of Peng's method to cope with quadrilinear interactions could even be interpreted in such a way as to mean that interactions of this sort do not exist—a statement which would be equivalent to the assumption that Fermi particles can only interact by means of a Bose field. (2n + 1) linear interaction terms must contain one Bose quantity at least, since Fermi field quantities are not observable and therefore can only enter the interaction term in bilinear form.

Non-Linear Interaction of MHD Waves with Small-Scale Ionospheric Irregularities

2004 ◽  
Vol 61 (7-12) ◽  
pp. 1055-1071
Author(s):  
N. N. Gerasimova ◽  
V. G. Sinitsin ◽  
Yu. M. Yampolski
Keyword(s):  
Ionospheric Irregularities ◽  
Mhd Waves ◽  
Small Scale ◽  
Linear Interaction ◽  
Non Linear

scholarly journals Validity of the Gender Dysphoria diagnosis and incidence trends in Sweden: a nationwide register study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Malin Indremo ◽  
Richard White ◽  
Thomas Frisell ◽  
Sven Cnattingius ◽  
Alkistis Skalkidou ◽  
...  
Keyword(s):  
Gender Dysphoria ◽  
Age Groups ◽  
Medical Intervention ◽  
Future Research ◽  
Advantages And Disadvantages ◽  
Incidence Trends ◽  
Interaction Terms ◽  
Definition Of ◽  
The Individual ◽  
Nationwide Register Study

AbstractThe aim of this study was to examine the validity of the Gender Dysphoria (GD) diagnoses in the Swedish National Patient Register (NPR), to discuss different register-based definitions of GD and to investigate incidence trends. We collected data on all individuals with registered GD diagnoses between 2001 and 2016 as well as data on the coverage in the NPR. We regarded gender confirming medical intervention (GCMI) as one proxy for a clinically valid diagnosis and calculated the positive predictive value (PPV) for receiving GCMI for increasing number of registered GD diagnoses. We assessed crude and coverage-adjusted time trends of GD during 2004–2015 with a Poisson regression, using assigned sex and age as interaction terms. The PPV for receiving GCMI was 68% for ≥ 1 and 79% for ≥ 4 GD-diagnoses. The incidence of GD was on average 35% higher with the definition of ≥ 1 compared to the definition of ≥ 4 diagnoses. The incidence of GD, defined as ≥ 4 diagnoses increased significantly during the study period and mostly in the age categories 10–17 and 18–30 years, even after adjusting for register coverage. We concluded that the validity of a single ICD code denoting clinical GD in the Swedish NPR can be questioned. For future research, we propose to carefully weight the advantages and disadvantages of different register-based definitions according to the individual study’s needs, the time periods involved and the age-groups under study.

scholarly journals Principal component regression in GAMLSS applied to Greek–German government bond yield spreads

2021 ◽  
pp. 1471082X2110229
Author(s):  
D. Stasinopoulos Mikis ◽  
A. Rigby Robert ◽  
Georgikopoulos Nikolaos ◽  
De Bastiani Fernanda
Keyword(s):  
Additive Model ◽  
Principal Component Regression ◽  
Principal Component ◽  
Complex Nature ◽  
Government Bond ◽  
German Government ◽  
Yield Spreads ◽  
Explanatory Variables ◽  
Interaction Terms ◽  
Bond Yield

A solution to the problem of having to deal with a large number of interrelated explanatory variables within a generalized additive model for location, scale and shape (GAMLSS) is given here using as an example the Greek–German government bond yield spreads from 25 April 2005 to 31 March 2010. Those were turbulent financial years, and in order to capture the spreads behaviour, a model has to be able to deal with the complex nature of the financial indicators used to predict the spreads. Fitting a model, using principal components regression of both main and first order interaction terms, for all the parameters of the assumed distribution of the response variable seems to produce promising results.

Sign in / Sign up

Export Citation Format

Share Document