Course : Analysis of experience plans MAT3378

Exersice : 1 In a study of mother-child interaction, trained observers observers rate mothers on the quality of their interactions with their young their interactions with their young child. Mothers were classified according to whether they were (primiparous or multiparous mothers) and according to the baby's birth weight (low birth weight (LBW) or very low birth weight (VLBW) or normal birth weight (PNN). The data represent scores on a 12-point scale: a higher score indicates a better mother-child interaction. The data are (10 observations per cells):

Birth weight	Primipares	Multiparous
LBW	4 6 5 3 3 3 4 3 3 6	3 4 3 3 6 7 1 4 4 4
VLBW	6 5 5 4 9 6 2 6 5 5	7 8 8 9 8 2 1 9 9 8
PNN	8 7 7 6 7 2 5 8 7 7	9 8 9 9 3 10 9 8 7 10

We want to perform a two-factor analysis of variance;

a) What are the hypotheses to be tested? (b)Perform a full analysis of variance, specifying the appropriate model and giving your conclusions. (c) If the interaction between the two factors is non-significant, perform an analysis of variance without this interaction and give your conclusion. (d) Which is the best model? Justify your answer.

Exersice : 2

Repeat the data from exercise 6, replacing the data in each by their mean value. The result will be a table with a single observation per cell. (a) Perform a full analysis of variance, specifying the appropriate model and giving your conclusions. (b) Compare your conclusion with that obtained in question (b) of exercise 6