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Chapter 11: Problem 23

Two different underground pipe coatings for preventing corrosion are to be compared. The effect of a coating (as measured by maximum depth of corrosion penetration on a piece of pipe) may vary with depth, orientation, soil type, pipe composition, etc. Describe how an experiment that filters out the effects of these extraneous factors could be carried out.

Short Answer

Expert verified
To isolate the effect of pipe coating on preventing corrosion, an experiment can be designed by utilizing control groups, randomization, and replication. All extraneous factors like depth, orientation, soil type, pipe composition should be evenly distributed or controlled in each group to ensure unbiased results. A control group should have no coating to measure the natural corrosion level, thus evaluating the effect of each coating type. The experiment should be repeated for reliable results, only after which corrosion levels should be analyzed statistically to derive significant conclusions.

Step by step solution

01

Identification of Factors

Firstly, identify all the factors that affect the experiment. In this scenario, these factors include the depth of the pipe, its orientation, soil type, and pipe composition.
02

Utilisation of Randomization

Use randomization to reduce the effect of extraneous factors. To do this, group a selection of pipes that are similar in their stated factors (like depth, orientation, soil type, and composition). Then apply the different coatings to each group, ensuring that each group contains all variants of coatings.
03

Using a Control Group

Implement a control group with no coating to measure the natural corrosion level and track the difference made by each coating type separately.
04

Replication

Repeating the experiment would help to establish if the results hold true across different instances. Multiple sets of similar pipes can be used for this.
05

Analysis of Data

After running the experiment for an appropriate period, assess the corrosion levels on each group of pipes. Here, statistical tests would help in determining if any observed differences in corrosion are statistically significant, or merely due to chance.

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