Pareto Bar Chart Doubt

[Kashyap Panchal]

In the video lecture, Prof. Usha mentioned that the Pareto Bar Chart could either be in the ascending or the descending order.

However, in the activity questions, the pareto bar chart being in the ascending order is an incorrect answer.

Is this a glitch? or the pareto chart can actually be only drawn in the descending order?

PFA a screenshot of the same.

[CG]

I also remember hearing this in lecture 2.2 and did not expect to get a score of 0 for selecting the 3 options you did. I figured I must have mis-heard then, however since you raised this here I searched the transcripts of lecture 2.2 and i'm posting a screenshot below.

Any way if you read up further on Pareto Charts you will find that a real Pareto chart actually has 2 y-axes on the left and right. The bars or frequency is sorted in descending order and its scale is on the left axis. The same graph also has a concave line that represents cumulative frequency. The purpose of such a chart is to illustrate Vilfredo Pareto's Principle (80 20 rule - 80 percent of problems caused by 20 percent of reasons. or 80 % or revenue from 20 % of consumers etc...). So taking care of the the items represented by the tallest few bars under the cumulative curve at point 80 will give good results.

You can read more about it on the wikipedia article on Pareto Charts. 

[CG]

It looks like the course team has updated the Week 2 Activity 2 in accordance with Week 2 Lecture 2. 

How did I find out ? 

If  you have already completed any activity, practice assignment or graded assignment and submitted it, the answers will be saved and show up next time you open the page. While referring the Week 2 Activity 2 to check a question to clear someone's doubt on the forum, I noticed that all the answers were unchecked/unsaved despite having solved and submitted them. So I answered them again.

This time I noticed that the system had been modified to accept "Pareto chart is same as bar chart if the frequency data is sorted in ascending order." as the correct answer.

Screenshot :

If the course team has done this silently, this reflects the ethics of the institution. The ethical thing to do would have been to notify everyone who submitted Week2 Activity 2 that such a modification has been done. This would be considered Responsible Disclosure.

If they have indeed notified everyone who submitted Week 2 Assignment 2, then I have not received any communication regarding the same. 

Thanks.

[Dhannya POD]

It was an oversight on our part not to have posted an announcement regarding the edits and it was not intentional.

We will issue a list of all edits shortly.

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Dhannya. S. M,

IITM Online Degree Project,

IIT Madras.

[CG]

Thank you for the clarification Dhannya.

It is important to notify such edits. In this case all those who originally marked the three choices and scored zero, would have re-calibrated their understanding and moved on, believing that Pareto charts can only be in descending order from the left vertical axis. Those who attempt this activity question at a later date (after the edit) will reinforce their understanding based on lecture 2.2 that Pareto charts can be in either descending or ascending order from the left vertical axis.

Looking forward to a list of all such edits. 

Thanks.

 

On Sunday, October 18, 2020 at 12:32:08 PM UTC+5:30, Dhannya OD Course Support wrote:

It was an oversight on our part not to have posted an announcement regarding the edits and it was not intentional.

We will issue a list of all edits shortly.

On Sat, Oct 17, 2020 at 4:11 PM CG <cheri...@gmail.com> wrote:

It looks like the course team has updated the Week 2 Activity 2 in accordance with Week 2 Lecture 2. 

How did I find out ? 

If  you have already completed any activity, practice assignment or graded assignment and submitted it, the answers will be saved and show up next time you open the page. While referring the Week 2 Activity 2 to check a question to clear someone's doubt on the forum, I noticed that all the answers were unchecked/unsaved despite having solved and submitted them. So I answered them again.

This time I noticed that the system had been modified to accept "Pareto chart is same as bar chart if the frequency data is sorted in ascending order." as the correct answer.

Screenshot :

If the course team has done this silently, this reflects the ethics of the institution. The ethical thing to do would have been to notify everyone who submitted Week2 Activity 2 that such a modification has been done. This would be considered Responsible Disclosure.

If they have indeed notified everyone who submitted Week 2 Assignment 2, then I have not received any communication regarding the same. 

Thanks.

On Wednesday, October 14, 2020 at 1:23:28 PM UTC+5:30, CG wrote:

I also remember hearing this in lecture 2.2 and did not expect to get a score of 0 for selecting the 3 options you did. I figured I must have mis-heard then, however since you raised this here I searched the transcripts of lecture 2.2 and i'm posting a screenshot below.

Any way if you read up further on Pareto Charts you will find that a real Pareto chart actually has 2 y-axes on the left and right. The bars or frequency is sorted in descending order and its scale is on the left axis. The same graph also has a concave line that represents cumulative frequency. The purpose of such a chart is to illustrate Vilfredo Pareto's Principle (80 20 rule - 80 percent of problems caused by 20 percent of reasons. or 80 % or revenue from 20 % of consumers etc...). So taking care of the the items represented by the tallest few bars under the cumulative curve at point 80 will give good results.

You can read more about it on the wikipedia article on Pareto Charts. 

On Wednesday, October 14, 2020 at 12:04:13 PM UTC+5:30, Kashyap Panchal wrote:

In the video lecture, Prof. Usha mentioned that the Pareto Bar Chart could either be in the ascending or the descending order.

However, in the activity questions, the pareto bar chart being in the ascending order is an incorrect answer.

Is this a glitch? or the pareto chart can actually be only drawn in the descending order?

PFA a screenshot of the same.

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