For those of you who attended my presentation at SIGiST 2008, below are the results of the Ambiguity Review exercise that you all did 🙂
Sorry about the length of this post – even by MY standards it’s a bit long. But if you’re into Quality in particular, and Requirements Engineering in particular, I think you’ll find it worthwhile.
So, What was the Exercise?
The goal was to find as many ambiguities as possible in the exercise below (the “Postal Regulations” text is courtesy of Gary Mogyorodi), and to re-write it, fixing the ambiguities:
You are a computer science student, and twice a week you work in the local Post Office. Two weeks ago the post ffice received new regulations, and all the employees in your branch start implementing the regulations. The manager of your branch quickly realized that the employees were making mistakes with the postal charges. Since you are the “technologist” of the branch, the manager asked you to explain to all the employees what the new regulations mean.
The Postal Regulation (Draft)
The following postal regulation determines postal surcharges. This regulation applies only to parcels, not other types of postal items, and only to parcels sent to South America. For parcels which people mail to South America between December 1 and December 24 of each year, the teller will apply these surcharges in addition to the standard postage
Country and Weight Surcharge
Argentina All weights 35 NIS
Brazil Weight > 33 pounds 70 NIS
Brazil Weight < 33 pounds 60 NIS
There were a number of ambiguities that almost everyone wrote, and there were a few that only some people thought of. Below is the complete list, with the unusual answers in bold. If the person who gave the bold answers wrote his/her name, they are mentioned by name :-). So, if you wrote one of those answers but forgot to tell me who you are, and you want your name added, send me a comment, and I will add you.
See how many of them you managed to find 🙂
And if you want to add more, that’s great – send me a comment, and I’ll add it to the list.
- Who pays for the surcharge – the sender or receiver?
- What is the surcharge for exactly 33 pounds?
- Does “between December 1 and December 24” include those dates or not?
- What is the “standard” postage?
- What about the other countries in South America, is there a surcharge for them?
- Does South America include Central America?
- What about the rest of the year, is there any surcharge?
- What happens if you mail something from home, i.e. there is no teller?
- The regulations don’t say that they apply to parcels sent from Israel to SA. Maybe they are from a different country?
- “For parcels which people mail”, what about companies? Do they have a surcharge? (from Shaul Weinstein of Intel, Janna Fridman of Intel, and Michael Stahl of Intel and Joshua Weiss of Intel Valor
- What about postal items that are not parcels?
- What is considered a parcel?
- What about the size or volume of parcels (is sized used to determine if something is a parcel)?
- What about special delivery items, do they have a surcharge?
- What about insurance, packaging, etc. is that included in the surcharge? Do they have a surcharge of their own? (this was from Efi, who wrote “what about insurance, packaging, etc.”. I added 2 possibilities of what he could have meant. Are there others?)
- Do the prices include VAT?
- “Each year” – who will remember it after the 1st year? (Leonid Z of Marvell)
- It’s confusing that Brazil is written twice in the list (Leonid Z of Marvell)
- Is there a difference between “send” and “mail”? If yes, explain, if no, use just one term (Gadi Shiloah of BMC, Michael Stahl and Joshua Weiss of Intel)
- Why is the surcharge required? (Gadi Shiloah of BMC) I liked this 🙂 , because Gadi used the “validation tool” that I explained in the first half of the presentation!
- Why does Argentina have a lower surcharge, and why is their a difference in weights for Brazil but not for Argentina? (Erez521 Erez Landwer of Interwise, outsourced from Sela) I liked this too 🙂 , because here also, Erez used the “validation tool” that I explained in the first half of the presentation!
- “The teller will apply …”, the use of the word “will” is ambiguous (Debi adds e.g. is this automatic, or does the teller have to add this by hand). I don’t know who wrote this, but it is really good. Another example of someone using something mentioned earlier in the presentation, but in this case, part of the ambiguity review explanation.
- It is not clear if the surcharge is per pound or for the whole pacakge. (Janna Fridman of Intel)
- The regulations are marked “Draft”, so it’s not clear whether they are final and when the regulations start being valid (Janna Fridman of Intel, Barak Benjo of NDS, and one other person who didn’t leave their name)
- The regulations use “pounds” which is not the measure used in Israel. There should be a conversion table (Janna Fridman of Intel)
- There is no maximum size or weight mentioned
- When does the surcharge start, from the moment the parcel is handed in? And what about companies that pay at the end of the month by credit? (Michael Stahl of Intel and Joshua Weiss of Intel Valor)
- “The teller” – does the surcharge apply if someone else, e.g. the branch manager, handles the parcel? (Michael Stahl of Intel and Joshua Weiss of Intel Valor)
- “The teller will apply the surcharges” – is this a separate payment, or part of the same payment? (Michael Stahl of Intel and Joshua Weiss of Intel Valor, and one other person who didn’t leave their name)
Firstly, you are all winners, since you all now have more tools to use when writing or reviewing requirements. The companies you work for are also winners, since they will get a return on their investment in sending you to this conference – you will find more bugs in the early stages of your projects, and will save them a lot of money.
But there are 3 people who had the most interesting list of unusual ambiguities.
They are ….. Michael Stahl and Janna Fridman, from Intel, and Joshua Weiss from Valor!
And there is an honourable mention to 2 people, who used lessons from the presentation in the exercise itself: Gaid Shiloah of BMC, and Erez521 of ?? (Erez – if you send me your name and company, I will update the post). Erez Landwer of Interwise, outsourced from Sela.
Well done, everyone, and thank you for taking part. I hope you found it useful.
And of course, many many thanks to all of you for voting my presentation as one of the top 3 of the day 🙂
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