Workshop $2$: Histograms and Descriptive Statistics

Practice Tools: Descriptive statistics and Histograms

Situation:

Suppose you work for a company that makes fruit flavored candy. The high season for candy is

around February $14$th$.$ Since there have been complaints with the product quality from

customers, you have been tasked with collecting data in the Measure Phase for the weight of

candies in a bag, to document the current performance of your production process. This data is

needed to establish a baseline measurement at the beginning of your Lean Six Sigma project so

that you will have a measurement to compare against later once the process has been

improved.

Instructions:

Use information from the Measure Phase Part $2-$Baseline Measurements Lessons to assist you

with the activities that follow. Be sure to follow the $$best practices$$ for each tool you use in this

workshop.

You collect a random sample of candies from your production process and measure the

diameter of each. You record your measurements in a spreadsheet in Microsoft Excel and use

Microsoft Excel to calculate your descriptive statistics and create a histogram of your data with

the Data Analysis ToolPak Excel add$-$in$.$ See the slides for instructions on how to install the free

Data Analysis ToolPak Excel add$-$in$.$ The use of Excel and the add$-$in are required for this

assignment.

Activities: $($also see next page$)$ The Workshop $2$ Excel Dataset must be used to complete the

assignment.

$1.$ For the candy produced by your production process, what is the:

a$.$ Average weight of candies in a bag in grams $($g$)?$

b$.$ Standard deviation in grams $($g$)?$

c$.$ Range in grams $($g$)?$

$2.$ Create a histogram that summarizes your data set $($i$.$e$.,$ measurements of candy

diameter in cm$)$: The data is in the dataset in the Workshop Resources for this

workshop. This is data for the $$as$-$is$$ process before any improvements are made.

$[$Paste your histogram here. Please ensure your work is readable on an $8(1)/(2)$ in$.$ x $11$ in$.$ piece of

paper or you will not receive credit for your work.$]$

$3.$ When the project is complete and you have implemented solutions to improve the

production process, the process performance is measured again by measuring the

amount of seasoning and get the following results:

Improved Packaging process results$-$Weight of candies in a bag:

Average: $62$ g; standard deviation: $2\mathrm{.}5$ g; range: $10$ g$.$

Based on the data from the changed process, has the process improved? Answer Yes or

No and why.

Hint: Perform a before and after comparison by comparing the baseline

measurements in Activity #$1$a$-$c of this Workshop with the measurements given in

this question.

$4.$ How well does the improved process fulfill the candy industry specifications below?

Industry Specifications for bag weight: $59+6$ grams $($lower specification limit: $53$ grams

and upper specification limit: $65$ grams$)$

Hint: Perform another comparison by comparing the measurements given in this

question to the customer specifications given in the $$Scenario$$ part of this Workshop.

Zoom

Weight Candy Bag $($g$)$

$58$

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$53$

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$58$

$59$