Creating Effective Spreadsheets

Challenge Blog

Multi-Dimensional Spreadsheet Challenge Blog

I’ll try to keep these statistics current. I used the country code of the email address of the participant, or information supplied in the email signature or personal knowledge. Those who have requested a Kit from a generic address can inform me of their country by sending me another email. Thanks.

I’m impressed: Australia has a very dynamic Excel community for its size, with 35 requests. That’s 40% of the total. (Is there something in the water! Or is it because their Summer is coming?) The UK has 8, Ireland has 3, the Netherlands, Poland and the US have 2 and the others have 1 each.

There is still a big number of Unknowns.

There are now 9 submission.

Number of Kit Requests by Country

Cumulative Number of Kit Requests and Submissions

2018-11-08 Macros and VBA

A few participants ask if they can use macros or VBA in their solution. YES, you can. But if you use old technology, like Excel 4.0, I may have to communicate directly with you (Skype or FaceTime) to get further explanations.

2018-11-04: No Rounding

A Challenge participant wonders why my formulas don’t round the results when they calculate integers, like unit sales.

There is always a debate about that. Here, we are dealing with forecasted estimates, and you can consider them as “expected averages”. Rounding an average is incorrect, even when the value doesn’t seem to make sense: the “average” family has 2,3 children. On the other hand, if you have a model that evaluates the number of electrical plants you need to supply a given population and you get 2,3, then you should round it up to 3.

In this case, I choose not to round the results. If you prefer to round them, then you will not be able to compare your results with mine. But I would not consider that your model is wrong: it’s just a developer’s choice.

2018-11-04: Error in one formula

In my 36-year university career, it happened a few times: I write an exam question and verify it, and verify it, and yet again… Then, during the exam, a student notices an error and tells the proctor who then calls me. By the time I correct it and make an announcement in the exam room, some students have finished the question without noticing it or have struggled because their result did not match the example. As you might expect, I always felt bad when that happened and I would always adapt my grading in favour of the students (depending on the gravity of the error.)

Well, one challenge participant noticed it early, and I hope the others were not inconvenienced by it. It has nothing to do with the spreadsheet structure: formula 9 (the one that calculates the expected demand from the price) in the Formula List does not correspond to the description in the problem statement. The one in the problem statement is the correct one and it is the one I used to produce the two dashboard examples in the main Challenge page. The Challenge Kit has been revised and all the participants who received the erroneous have been sent the revised Formula List. The new Formula list is named Acme TechnoWidget Company - Formula List V3.pdf.

2018-11-01 : Announcement

The Multi-Dimensional Spreadsheet Challenge is announced. Click on the button: