beta weights
Parameter estimates from statistical models representing magnitude of activation or effect size.
Full Definition
Beta weights (or beta coefficients) are parameter estimates derived from statistical models that quantify the magnitude and direction of brain activation or other measured effects in neuroimaging analyses. In the context of the general linear model commonly used in fMRI analysis, beta weights represent the estimated change in BOLD signal associated with experimental conditions or covariates. These values are essential for second-level group analyses, effect size estimation, and quantitative comparisons between conditions or groups. Beta weights are typically extracted from regions of interest or used to create statistical parametric maps that show the strength of effects across the brain.
Usage
Usage note: Use plural 'weights' when referring to multiple parameter estimates; distinguish from other statistical measures.
In Context
- "Beta weights were extracted from the ROI for correlation analysis with behavioral measures." — fMRI analysis methods section
- "The group comparison revealed significantly different beta weights in the prefrontal cortex (p < 0.01)." — Statistical analysis results