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Question on pareto plots

Hi Guys,

I have four columns in my data table. They are:
Name, Total,Count and %.

The % column is calculated as Count/Total. The name has test1, test2, etc.

Here is an example:

Name Total Count %
Test1 5666 666 11.75
Test2 777 23 2.96
Test3 888 22 2.47

I am trying to plot a pareto with Count on the Y axis and Name on the X axis. I have got it working and it shows me the counts for all the tests in the form of bars arranged in a descending format.

I want to see % instead of counts. I used the red triangle to convert it into a % scale and it showed the % but they were calculated say for test1 it should me 93% instead of 11.75%.

I want to see a pareto which has the test names on the X axis with the bars plotted from highest % (of Total) to lowest %.

How can I do that?

Re: Question on pareto plots

The Pareto platform is producing a sensible answer for the data that you are giving it. It is looking at your count data and telling you that of all the counts, test1 accounts for 93%. A pareto analysis expects the cummulative probability to sum to 100% - but that is not what you are asking for. Put another way, it expects all of the counts to be generated from the same sample of data e.g. number of counts by classification of defect for a batch of products. You data is more like a count of defects from 3 separate batches. What you want to do is to produce a graphical representation of the counts for the different groups. You could use the Chart platform to plot the percentages that you have calculated: use the "Data" statistic computed on your % column, with name as the category.

Re: Question on pareto plots

Ok thanks for the info. I used a chart option and it worked. How do I get the bars to be sorted in a descending order? I want the highest % to show up as the leftmost bar.

Re: Question on pareto plots

That's a good point! Sorting the data table by the % column doesn't change the display order of the bars. I don't know if there is another way??

So, plan B. Back to the pareto plot. There is a "weight" role in the pareto plot dialog. You can use this role to adjust for the fact that the different counts are derived from different size totals. Create a new column and call it something like weight. Assign the following formula

weight = 1 / total

(or weight = 100 / total ) depending on whether you want fractions or percentages.

Assign column 'name' to 'y,cause'
Assign column 'weight' to 'weight'
Assign column 'count' to 'freq'



Jun 23, 2011

Re: Question on pareto plots

You can assign the column property "Row Order Levels" to your "Name" column.
Do the chart after the sort. Chart will display the groups in the order they appear in the data table.