lambdaväärtus

The term lambdaväärtus, often translated as lambda value, refers to a concept in statistical modeling and econometrics, particularly in the context of generalized linear models (GLMs) and their extensions. It represents a parameter that quantifies the effect of a predictor variable on the response variable when the relationship is modeled on a different scale.

In many GLMs, the expected value of the response variable is related to a linear predictor through a link function. The lambda value can be interpreted as the change in the expected value of the response variable for a one-unit change in a predictor, holding other predictors constant, when this change is considered on the scale of the linear predictor. It is crucial for understanding the magnitude and direction of influence of individual predictors.

For example, in a Poisson regression model used for count data, the link function is typically the natural logarithm. If lambda represents the coefficient for a predictor, then a one-unit increase in that predictor corresponds to a lambda-unit increase on the log scale of the expected count. Exponentiating the lambda value then provides the multiplicative effect on the expected count itself. Different modeling frameworks might use slightly varying definitions or interpretations of lambdaväärtus, but the core idea revolves around quantifying parameter effects within a specific, often transformed, scale of measurement.