From Yates Algorithm to Multidimensional Smoothing with GLAM Iain Currie
Heriot Watt University with James Kirkby, Maria Durban & Paul Eilers University of Edinburgh December, 2006
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Plan of talk
- Classical regression
- Factorial designs and Yates algorithm
- Yates algorithm as an array computation
- Generalised linear models
- Array regression
- Examples
Themes
- Structure of data and models
- Algorithms
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Classical regression
Structure
- Data: a data vector y, n × 1
- Model: a model matrix X, n × c
a parameter vector θ, c × 1 µ = E(y) = Xθ
- Error distribution: normal
Algorithm
- Normal equations
X′X ˆ θ = X′y
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Classical regression
Universal recipe
Fit <- lm(y ∼ X - 1)
A model algebra
Fit <- lm(y ∼ x + x2) Fit <- lm(y ∼ A + B + A:B) Fit <- lm(y ∼ x + x2 + A∗B)
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