Does the type of cooking pot affect iron content? Iron-deficiency anemia is the most common form of malnutrition in developing countries, affecting about 50% of children and women and 25% of men. Iron pots for cooking foods had traditionally been used in many of these countries, but they have been largely replaced by aluminum pots, which are cheaper and lighter.
Some research has suggested that food cooked in iron pots will contain more iron than food cooked in other types of pots. One study designed to investigate this issue compared the iron content of some Ethiopian foods cooked in aluminum, clay, and iron pots.17 One of the foods was yesiga wet', beef cut into small pieces and prepared with several Ethiopian spices. The iron content of four samples of yesiga wet' cooked in each of the three types of pots follows. The units are milligrams of iron per 100 grams of cooked food.
(a) Make a table giving the sample size, mean, and standard deviation for each type of pot. Is it reasonable to pool the variances? Note that with the small sample sizes in this experiment, we expect a large amount of variability in the sample standard deviations.
(b) Run the analysis of variance. Report the F statistic with its degrees of freedom and P-value. What do you conclude?