Question

The study was to identify the role of various disease states and additional risk factors in the development of thrombosis. One focus of the study was to determine if there were differing levels of the anticardiolipin antibody IgG in subjects with and without thrombosis.

Table summarizes

Group	Mean of IgG	Sample size	Standard Deviation
Thrombosis (1)	68	57	47
No  thrombosis (2)	45	52	32

We wish to know if we may conclude, on the basis of these results, that, in general, persons with thrombosis have, on the average, higher IgG levels than persons without thrombosis with α = 0.05.

1. Write the hypotheses, indicate the claim

2. find the critical value z-value

3. calculate the standardized z -value

4. what is the decision

Answer 1