Consider a CRD with a predictor that has 4 levels.
Write out the model form, clearly identifying notation, and what the form of the expected mean of each level (in terms of the model parameters you used).

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.