New Process For Producing Synthetic Diamond
New Process For Producing Synthetic Diamon
Due Wednesday at noon 1200 A new process for producing synthetic diamonds can be operated at a profitable level only if the average weight of the diamonds produced by the process is greater than 0.5 karat. To evaluate the profitability of the process, a sample of six diamonds was generated using this new process, with recorded weights 0.46, 0.61, 0.52, 0.48, 0.57, and 0.54 karat. Do the six measurements present sufficient evidence to indicate that the average weight of the diamonds produced by the new process is in excess of 0.5 karat? To answer this question conduct an appropriate test of hypothesis using the five step process outlined in our textbook and utilized in the solutions to the Chapter 8 review problems, which can be accessed via the link in the Assignments, Tests & Quizzes sub-section in the weekly lesson that can be found in the Lessons section of our classroom. Keep in mind that your post must be made by 11:55PM EASTERN time on Wednesday during the week in which a discussion question is posed. I will evaluate your responses to each of these questions using a 0 to 10 point scale, and your contribution to each of the Discussion Forums will count as 1.25 percent of the overall course grade for a total of 10 percent. My evaluation of your post will be based on the extent to which you participated and fostered a positive and effective learning environment--for yourself and others. Participating and sharing are the keys. Naturally, simply copying someone else's post is prohibited.
Paper For Above instruction
Introduction
The production of synthetic diamonds has become an increasingly profitable industry, driven by advancements in material science and manufacturing techniques. An essential aspect of maintaining profitability is verifying whether new production processes yield diamonds of sufficient weight—specifically, greater than 0.5 karats. To assess this, a hypothesis testing approach is necessary, using sample data to make inferences about the true mean weight of diamonds produced by the process.
Methodology
The core of the investigation involves conducting a one-sample t-test for the mean. The null hypothesis (\(H_0\)) posits that the mean weight of the diamonds (\(\mu\)) is less than or equal to 0.5 karats, while the alternative hypothesis (\(H_a\)) suggests that \(\mu\) exceeds 0.5 karats. Mathematically:
- \(H_0: \mu \leq 0.5\)
- \(H_a: \mu > 0.5\)
The sample data consists of six diameters: 0.46, 0.61, 0.52, 0.48, 0.57, and 0.54 karats. This data will be used to calculate the sample mean and standard deviation, which serve as inputs for the t-test.
The justification for using a t-test hinges on the small sample size and the assumption that the weights are approximately normally distributed. Since the sample size is small (n=6), the t-distribution provides an appropriate framework for statistical inference.
Calculation and Analysis
Calculating the sample mean:
\[
\bar{x} = \frac{0.46 + 0.61 + 0.52 + 0.48 + 0.57 + 0.54}{6} = \frac{3.18}{6} = 0.53 \text{ karats}
\]
Calculating the sample standard deviation:
\[
s = \sqrt{\frac{\sum (x_i - \bar{x})^2}{n-1}}
\]
where,
\[
\sum (x_i - \bar{x})^2 = (0.46-0.53)^2 + (0.61-0.53)^2 + (0.52-0.53)^2 + (0.48-0.53)^2 + (0.57-0.53)^2 + (0.54-0.53)^2
\]
\[
= (-0.07)^2 + (0.08)^2 + (-0.01)^2 + (-0.05)^2 + (0.04)^2 + (0.01)^2
\]
\[
= 0.0049 + 0.0064 + 0.0001 + 0.0025 + 0.0016 + 0.0001 = 0.0156
\]
\[
s = \sqrt{\frac{0.0156}{5}} = \sqrt{0.00312} \approx 0.0559
\]
Next, compute the t-statistic:
\[
t = \frac{\bar{x} - \mu_0}{s / \sqrt{n}} = \frac{0.53 - 0.5}{0.0559 / \sqrt{6}} \approx \frac{0.03}{0.0228} \approx 1.32
\]
where \(\mu_0 = 0.5\) is the hypothesized population mean.
Using a significance level (\(\alpha\)) of 0.05 and degrees of freedom \(df=5\), the critical t-value for a one-tailed test is approximately 2.015 (from t-distribution tables).
Since the calculated t-value (1.32) is less than 2.015, we fail to reject the null hypothesis at the 5% significance level.
Discussion of Rationale
The chosen hypothesis test—specifically, a one-sample t-test—adequately addresses the research question because of the small sample size and unknown population standard deviation. The null hypothesis reflects the threshold for profitability, i.e., an average weight of more than 0.5 karats. The sample mean of 0.53 karats suggests that, on average, the diamonds are slightly above this threshold, but the statistical test indicates that this difference is not statistically significant at conventional levels.
This decision to fail to reject \(H_0\) implies that there isn't sufficient evidence from this sample to confirm that the average weight exceeds 0.5 karats with high confidence. However, the proximity of the t-value to the critical value suggests that collecting a larger sample might produce more definitive results, reducing the margin of error and increasing the power of the test.
Conclusion
Based on the hypothesis test performed, the data from this small sample do not provide strong enough evidence to conclude that the new process produces diamonds with an average weight exceeding 0.5 karats at the 5% significance level. While the sample mean is slightly above 0.5, the variability and small sample size limit the strength of this conclusion. This analysis underscores the importance of larger sample sizes in manufacturing quality assessments and the need for ongoing testing to confidently evaluate process profitability.
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