Question

The ceramic tile used in the construction of the floors in a mall must be sturdy, easy to clean, and long-lasting. Before installing a specific type of tile, a construction firm orders a box of 25 of the proposed type of tile and uses a standard strength test on each tile in the box. The standard breaking test consists of someone putting each tile half way on a table in a specialized way and then placing standardized weights on the part of the tile that is not on the table until the tile breaks. The results are used to determine whether this type of tile will be used throughout the new mall.

a)Is this an observational or an experimental study? Please explain your answer.

b)What is the sample in this problem?
1. All tiles of this type.
2. 25 tiles of any type of tiles used on floors in malls.
3. The 25 tiles of this type.
4. All tiles used on floors in malls.

c) Is this sample random? If so, justify your answer. If not, describe a possible technique that could be used to obtain a random sample.

Answer 1

a) An observational study is a study where researchers simply collect data based on what is seen and heard and infer based on the data collected. The researcher has no control over the variables in an observational study. An experiment is a method of applying treatments to a group and recording the effects.

THIS IS EXPERIMENTAL STUDY, AS EXPERIMENT IS BEING PERFORMED ON A GROUP

b) 3. The 25 tiles of this type.

c) Yes , it is a random sample, as a random sample of 25 tiles is selected and then that experiment is performed on each of them.