Alexandru Bogdan Teiusanu (alete812)
Essay by kamen15 • February 19, 2019 • Term Paper • 616 Words (3 Pages) • 501 Views
Assignment 3 – Team 7A
Alexandru Bogdan Teiusanu (alete812)
Min Seok Jang (minja881)
Pranay Kumar Boppuri (prabo425)
Venkata Naga Sai Prithvi Chakkirala (vench027)
In the following report we are presenting the processed data and conclusions we draw from the set of data we received regarding some specific quality issues that were reported in the quality coffee’s production chain.
Normal distribution
The problem reported is related to the liquid volume in the bottles, and two samples of 250 bottles each were measured, and the each bottle’s volume recorded in an Excel file that we received.
The two samples are from two different periods.
We plotted to see if the data is normally distributed. The results are as following: [pic 1]
The chart is displaying a line-like shape, so we consider it reveals a normal distribution.
This chart is revealing a normal distribution in the collected data. You can notice this line-like shape again, which indicates this normal distribution.[pic 2]
Average and dispersion control charts
The first period shows a normal process, in statistical control. There are no peaks, loops, patterns. Everything seems to have gone right, as expected and planned. The values are normal, distributed around the mean[pic 3][pic 4][pic 5]
In this second period we can definitely observe some red flags, we have peaks in the Xbar, Rbar and Sbar charts. It is not sufficient data to say why they happen, but there are definitely some anomalies and the process is not in statistical control due to these peaks over the limits.[pic 6][pic 7][pic 8]
Histogram [pic 9]
The centration is good, but the dispertion could be improved, as one can see in the histogram above.
The capability Cp is 0.348148 and Cpk is 0.313333. This is very bad, and it translated in high dispertion. The process has good stability, but the dispertion is too high, therefore our reccomendation is to decrease the dispertion.
Correlation Chart[pic 10]
Y=0.2121x - 68.516
R² = 0.8259
Our conclusions after creating this correlation chart displayed above are that there is a strong correlation as R² is almost equal to 1. Even though the capability was bad during the first period, the customers didn't complain because the taste and the filling level were good.
Pareto chart[pic 11][pic 12]
Considering the Pareto Chart, 33.33% of all categories of problems (the first 5 categories) sums up 61.90% of the total amount of problems.
The main important issues discovered are:
- Opening torque too hard
- Broken opening string
- Marks on the container
- Dents in the container
- Broken container
We believe there is enough evidence here to make a visit at the packing process. It is definitely something going wrong there.
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