Additive effect often occurs when two similar drugs are taken together to achieve the same degree of therapeutic effect while reducing the specific adverse effect of one particular drug. For example, aspirin, paracetamol, and caffeine are formulated together to treat pain caused by tension headaches and migraine.
What is an additive effect?
An additive effect refers to the role of a variable in an estimated model. A variable that has an additive effect can merely be added to the other terms in a model to determine its effect on the independent variable.
What is a 'treatment effect?
A ‘treatment effect’ is the average causal effect of a binary (0–1) variable on an outcome variable of scientific or policy interest. The term ‘treatment effect’ originates in a medical literature concerned with the causal effects of binary, yes-or-no ‘treatments’, such as an experimental drug or a new surgical procedure.
Does the regression model contain additive effects?
For example, our regression model for the birth weights of babies contains additive effects, because the response function can be written as a sum of functions of the predictor variables:
What is the additive model of EEG?
The signals X 1 and X 2 recorded at these two EEG electrodes can be expressed by the following additive model: This additive model is based on a basic assumption that a scalp EEG is a linear combination of source components.
What is the meaning of additive model?
In statistics, an additive model (AM) is a nonparametric regression method. It was suggested by Jerome H. Friedman and Werner Stuetzle (1981) and is an essential part of the ACE algorithm. The AM uses a one-dimensional smoother to build a restricted class of nonparametric regression models.
What is an additive effect in psychology?
the joint effect of two or more independent variables on a dependent variable where this is equal to the sum of their individual effects: The value of either independent variable is unconditional upon the value of the other and there is no interaction effect.
What does it mean factor effects are additive?
With the Additive Factor Method, if two experimental factors selectively influence two different stages by increments, the factors will have additive effects on reaction time. An assumption of the Additive Factor Method is that if two experimental factors interact, then they influence the same stage.
What is the difference between additive effects and interaction effects?
-My definition of statistical interaction: "Statistical interaction means the effect of one independent variable(s) on the dependent variable depends on the value of another independent variable(s)." Conversely, "Additivity means that the effect of one independent variable(s) on the dependent variable does NOT depend ...
What is the additive effect of drugs?
An additive effect is generally considered as the baseline effect for synergy detection methods. It is the effect that is theoretically expected from the combination of multiple drugs when synergy is not present.
What is additive and synergistic effects?
An additive effect refers to a food combination that provides the sum of the effects of the individual components; a synergistic effect occurs when the effect is greater than the sum of individual components, and antagonism occurs when the sum of the effects is less than the mathematical sum that would be predicted ...
What is an additive model in statistics?
In statistics, a generalized additive model (GAM) is a generalized linear model in which the linear response variable depends linearly on unknown smooth functions of some predictor variables, and interest focuses on inference about these smooth functions.
What is a non additive model?
Non-Additive. 1. The Non-Additive (Saturated) Model: In the non-additive model, the effects of one. factor are possibly different at all levels of the other factor → there is interaction. Essentially, the separate lines model in multiple regression.
Is the additive model plausible?
(c) The additive model is plausible, as the interaction term is not statistically significant at the standard α level.
What is an additive drug interaction?
Additive - Occurs when two or more drugs combine to produce an effect greater than effect of either drug taken alone.
What does additive interaction mean?
An additive interaction is defined as the differential reduction in absolute risk associated with one factor between different levels of the other factor. A stratified two-phase case-control design is commonly used in epidemiology to reduce the cost of assembling covariates.
What is additive effect biology?
Additive genetic effects: A mechanism of quantitative inheritance such that the combined effects of genetic alleles at two or more gene loci are equal to the sum of their individual effects.
What is the form of additive modeling?
For additive modeling of measurement errors, the simple linear regression model (linear combination of x) has the form
What are the three models of stressors?
There are three common models to describe the outcome of multiple stressors on biological systems: (1) the additive model , in which the response is equal to the sum of the effects of the individual stressors ; (2) the antagonistic model , when the combined effect is less than the sum of the effects of the individual stressors; and (3) the synergistic model , in which the response to exposure to multiple stressors is greater than the sum of the effects of the individual stressors ( Crain et al., 2008 ). Multiple stressors acting simultaneously also have the potential to interact, driving changes that are not at all predictable from the effects of single stressors (“ecological surprises” in the sense of Paine, Tegner, & Johnson, 1998 ). Such uncertainty reduces the predictive value of models of biodiversity change ( Darling & Côté, 2008 ).
Is Gaussian noise additive?
For instance, Gaussian noise is usually considered to be an additive component.
Can bipolar derivation remove additive background noise?
Thus, the bipolar derivation can remove the shared additive background noise between two “active” electrodes.
New Developments in Econometric Methods for Labor Market Analysis
The traditional selection bias model in econometrics began with the work of Heckman (1974) on wages and labor supply and was developed, expanded, and elaborated further in a series of papers in the late 1970s by Heckman (1978, 1979), Lee (1979), and others.
Financial liberalization and stock markets efficiency: New evidence from emerging economies
In order to determine the impact of financial liberalization on informational efficiency, we use the treatment effects methodology developed by Maddala (1983)7. This methodology has been used widely in the literature, especially in the areas of economic growth and social economics ( Maeda, 2008; Ranciere et al., 2006 ).
Income shocks, coping strategies, and consumption smoothing: An application to Indonesian data
In this section we present the empirical strategy that we adopt to obtain a quantitative measure of the income reduction produced by the crop loss, and of the household's ability to recover from the shock. Several methodologies have been used to measure income shocks.
Abstract
In clinical and epidemiologic studies of time to event, the treatment effect is often of direct interest, and the treatment effect is not constant over time. In this paper, the authors propose an estimator for the cumulative hazard difference under a stratified additive hazards model.
Author information
Institute of Applied Mathematics, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing, 100190, China
