/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 69 A manufacturer of clay roofing t... [FREE SOLUTION] | 91影视

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A manufacturer of clay roofing tiles would like to investigate the effect of clay type on the proportion of tiles that crack in the kiln during firing. Two different types of clay are to be considered. One hundred tiles can be placed in the kiln at any one time. Firing temperature varies slightly at different locations in the kiln, and firing temperature may also affect cracking. Discuss the design of an experiment to collect information that could be used to decide between the two clay types. How does your proposed design deal with the extraneous factor temperature?

Short Answer

Expert verified
The design of the experiment involves a randomized block design where block is each kiln with 50 tiles of each clay type. To handle the extraneous factor, temperature, tiles should be randomly placed inside the kiln or a temperature control system can be used.

Step by step solution

01

Understanding the Problem

Firstly, understand the problem requirement. The task is to design an experiment to test the effect of clay type on the proportion of tiles that crack during firing. However, it's recognized that temperature is an extraneous factor which means, it may affect the outcome but it's not the main factor being investigated.
02

Design the Experiment

Next, make a plan to test the effects of clay type. An effective way is to arrange a randomized block design experiment. Here, the block is the kiln. Within each kiln, tiles made from both clay types should be placed. So, every kiln will contain 50 tiles made from each clay type. This minimizes the effect of temperature variations within each kiln as both types are exposed to the same conditions.
03

Handle the Extraneous Factor

Lastly, to deal with the extraneous factor, temperature, a temperature-control system can be adopted, or the tiles should be placed in different parts of the kiln in every new cycle, to avoid any bias brought by temperature differences inside each kiln.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Randomized Block Design
The randomized block design (RBD) is a type of experimental design that's particularly useful when dealing with extraneous variables known to have an effect on the dependent variable. Imagine you're testing two brands of fertilizer on plant growth but you're aware that soil type might affect growth as well. An RBD would have you grouping plants based on soil type first (creating blocks), and then randomly assigning different fertilizer treatments within these blocks.

In the context of the tile cracking experiment, the kiln鈥攚ith its variable temperatures鈥攁cts as our 'block'. To ensure each type of clay is equally subjected to the various temperature conditions, a similar number of tiles from both types of clay are placed together in each block of the kiln. This method doesn't eliminate the influence of temperature but distributes its impact evenly across both clay types, thus allowing a clearer comparison of their inherent qualities.

For our tile manufacturer, employing an RBD means that every firing cycle within the kiln becomes a miniature experiment in itself. By systematically rotating the position of tiles made from each clay type within different parts of the kiln, we can assess the effect of clay type on cracking without worrying too much about temperature skewing the results.
Extraneous Factors in Experiments
Extraneous factors can be a thorn in the side of any experiment. These are variables other than the independent variable that might affect the outcome of the experiment, known as the dependent variable. Consider you鈥檙e running an experiment to see if a new teaching method improves student performance. If you overlook the factor of previous knowledge, you might wrongly attribute any improvement to your new method, whereas it could be due to the students鈥 already strong grasp of the topic.

In the tile cracking experiment, temperature is an extraneous factor. If it's true that temperature variations within the kiln affect tile cracking, these variations must be accounted for to avoid confounding results. By using the RBD, each kiln 鈥渂lock鈥 controls temperature differences by exposing both types of clay to the same range of temperatures.

Another step that can be taken is to use statistical control methods post-experiment to adjust for extraneous variables. This might involve analyzing the data using techniques like analysis of covariance (ANCOVA), which can adjust the dependent variable for the influence of the extraneous factor.
Effect of Clay Type on Tile Cracking
Tile cracking during firing is a significant issue faced by manufacturers. It鈥檚 a costly problem as it leads to wasted materials and time. The type of clay used may inherently influence the rate at which tiles crack in the kiln, with factors like impurities, grain size, and moisture content playing a role.

To isolate the effect of clay type, an experiment could be structured to compare the cracking between two different clays. With variables such as kiln position and temperature controlled within blocks, any differences in the cracking rate can more confidently be attributed to the clay type itself. For example, if despite random placement within the kiln and consistent firing practices, one type of clay consistently shows a higher cracking rate, we can infer that the composition or properties of the clay contribute to this outcome.

It's crucial for the tile manufacturer to quantify this effect to make informed decisions about materials. Not only does this kind of experiment illuminate which clay might be superior in reducing cracking, but it also contributes to a broader understanding of the material properties that are key to the production process.

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