Search results
Results from the WOW.Com Content Network
Another way to analyze hierarchical data would be through a random-coefficients model. This model assumes that each group has a different regression model—with its own intercept and slope. [5] Because groups are sampled, the model assumes that the intercepts and slopes are also randomly sampled from a population of group intercepts and slopes.
In econometrics, a random effects model, also called a variance components model, is a statistical model where the model parameters are random variables. It is a kind of hierarchical linear model , which assumes that the data being analysed are drawn from a hierarchy of different populations whose differences relate to that hierarchy.
When random coefficients are specified, each subject has its own regression equation, making it possible to evaluate whether subjects differ in their means and/or response patterns over time. Estimation Procedures & Comparing Models: These procedures are identical to those used in multilevel analysis where subjects are clustered in groups.
The model for the response is , = + + with Y i,j being any observation for which X 1 = i (i and j denote the level of the factor and the replication within the level of the factor, respectively) μ (or mu) is the general location parameter; T i is the effect of having treatment level i
The model assumes that there are two potential outcomes for each unit in the study: the outcome if the unit receives the treatment and the outcome if the unit does not receive the treatment. The difference between these two potential outcomes is known as the treatment effect, which is the causal effect of the treatment on the outcome.
Regression models predict a value of the Y variable given known values of the X variables. Prediction within the range of values in the dataset used for model-fitting is known informally as interpolation. Prediction outside this range of the data is known as extrapolation. Performing extrapolation relies strongly on the regression assumptions.
If an underlying random coefficient model is incorrectly specified as a random intercept model, the design effect can be seriously understated. In contrast, the OLS estimator of the regression slope and the design effect calculated from a design-based perspective are robust to misspecification of the variance structure, making them more ...
Retrieved from "https://en.wikipedia.org/w/index.php?title=Random_coefficient_model&oldid=364209635"