One Way Anova vs Two Way Anova
One way Anova and Two way Anova differ in terms of their purpose and concept. The purpose of one way Anova is to verify whether the data collected from different sources converge on a common mean. In other words it can be said that the purpose of one way Anova is find out whether the groups carried out the same procedures in conducting research.
On the other hand the purpose of the two way Anova is to verify whether the data collected from different sources coverage on a common mean based on two categories of defining characteristics. On the contrary the one way Anova uses only one category of defining characteristics to carry out its procedure.
The test for the presence of an item in a sample selected at random is the example for one way Anova. The process of choosing a sample from different sources at random gets repeated in the case of one way Anova. On the other hand let us take for example a steel company that has two factories each making three models of a product made of steel. It is now reasonable to ask whether the durability of the product varies from factory to factory as well as from model to model.
The other way of distinguishing one way Anova from two way Anova is that the one way Anova is used for a single factor between subject designs. In other words it can be said that it is meant for two or more treatment means.
On the other hand two way Anova is used in the comparison of treatment means. This involves the introduction of randomized block design. The experiment conducted in the case of two way Anova gets split normally into many mini experiments. In short it can be said that the two way Anova is employed for a design with two or more treatment means that can be called factorial designs.
There can be any number of levels in the case of one way Anova. It deals only with one factor such as treatment or group. On the other hand the treatment is called as fixed effects in the case of two way Anova. In both the cases it is interesting to note that the calculations are usually done by the computer. In order to find how the calculations are done it is quite natural that long hand is also occasionally employed.