Two Hour Parking
Signs such as this one are a common sight in Seattle's residential neighborhoods. I imagine the transportation department believes it to be clear and unambiguous. I beg to differ.
Your assignment for this week is to devise as many different interpretations of this sign as you can. Put your answers in the comments below or send them directly to me. I will post my answers (forty of them, plus another seventeen questions) next week, plus also explain what this exercise has to do with testing.
So what are you waiting for? Get busy!
*** Want a fun job on a great team? I need a tester! Interested? Let's talk: Michael dot J dot Hunter at microsoft dot com. Great testing and coding skills required.
Comments
- Anonymous
January 16, 2008
Boy, that's a tough one, since there are so many different combinations of those statements that are possible. Starting with the number "2":
- One may park here between 7AM and 6PM for 2 hours.
- This is sign number 2 of a given series. One may park here for an hour between 7AM and 6PM.
- This sign is incomplete. There is a sign one, and it offers quite clear notes on parking, which ran over onto this sign, number two, which explains why the first statement is cut off at hour. Moving to the time span:
- One may only park in this area between 7AM and 6PM. Parking outside that time span is forbidden.
- Parking is only restricted to the given time span between 7AM and 6PM.
- One may park at 7AM or at 6PM for the given time span, but at no other times (the dash has an ambiguous meaning, as we'll see when looking at Sun.-Hol) Moving to the first exception:
- Ignore all parking restrictions on SUN.-HOL.
- There is no parking at all on SUN.-HOL.
- On SUN.-HOL there is parking, but only for the given amount of time.
- If you park your car here on SUN.-HOL, you can leave it as long as want, locking you in for a permanent parking spot if your car breaks down. The meaning of SUN.-HOL:
- The exception (whatever it is) is applicable only on Sundays and Holidays.
- The exception is applicable when the weather sunny or during a nuclear holocaust.
- The exception is applicable for all days between Sundays and holidays (inclusive).
- The exception is applicable for all days between Sundays and holidays (exclusive). Finally, the last exception:
- Parking is not restricted in any way if you have a Zone 4 permit.
- Parking is not permissible ever if you have a zone 4 permit.
- The first exception is not applicable if you have a zone four permit.
- The first exception is always applicable if you have a zone four permit.
- This area is Zone 4 (whatever that means), except where permits are posted (Zone 4 is a different font; is it in the middle of the statement or does the exception wrap around it?) By assembling combinations of these 5 choices, I see 720 combinations, with many more possible. Suddenly I feel much less worried about where I park; this would make for an interesting day in court.
Anonymous
January 16, 2008
The comment has been removedAnonymous
January 16, 2008
This is pretty clear. 99% of people who drive would understand this to mean: 2 hour parking between 7AM and 6PM. Parking is uncontrolled outside those hours or on Sundays and Holidays. This restriction does not apply to vehicles with Zone 4 permits. That's pretty clean.Anonymous
January 16, 2008
The comment has been removedAnonymous
January 16, 2008
And that Bobbie is why you work as a programmer and not a tester...Anonymous
January 17, 2008
@Bobbie the Programmer: but then again, that's us programming guys not thinking beyond the obvious :-) We have to leave it to the test guys (see David's comment) to see if what we make is as obvious as we think. I'm definitely not a tester but far too often I thought to understand what the customer meant, only to find out later that it was a complete misunderstanding...Anonymous
January 17, 2008
Reminds me of my favorite sign in Cincinnati: "LANE ENDS EXCEPT 4-6 pm Mon-Fri" The first time I saw that, I was baffled: "So where do they put the lane when it's not 4-6pm Mon-Fri?" [What it actually means, of course, is that it's OK to park in that lane...except during evening rush hour.]Anonymous
January 17, 2008
Parking, the act, if it occurred before 7am is okay, right? Are Zone 4 permit holders forbidden from parking there even on holidays and Sundays? It appears as though I could park my car at 4pm and leave it until 9am the next day.Anonymous
January 18, 2008
Zach and David: Yay you for so many possibilities! Including a few I hadn't thought of - most excellent!Anonymous
January 19, 2008
Thought of one recently, but was unable to enter it in tonight: "Parking" could be imply that I cannot park the vehicle in some location for a particular amount of time during certain days of the year. "Parking" could imply that someone else can park my vehicle in some location for a particular amount of time during certain days of the year. Thanks for the mental exercise!Anonymous
January 19, 2008
When I saw this post I thought about how to approach this. You can define all kinds of scenarios with certain values. Argue about the meaning of dashes and abbreviation etc. During thinking I made the assumption that these are rules. As in systems we could call them business rules. Only when would business rules make some sence in a system? When they are actually executed and most important if the outcome is checked. The goal of this sign is the prevent people to park at certain timeslots. If they behave badly and the officer comes around they get a ticket. And here is the missing information: When does the officer comes around? If there is no officer then there will be no ticket and therefor no pain and we could park anytime. Related to systems: why should we test business rules if they are not triggered and not controlled? Related to the sign: I would start checking if there is an officer. If not then what ever you do, the result will never be a ticket/thow-away of your car. If there is an officer, check how what the frquency will be when he does his duty? After you did this, make sure he has his ticket book available and not full, or his mobile to call the thow-away car. And if all is according the rules, then we might also look at the circumstances. Asume it is your car, only it was stolen and someone else placed it there. Do you have to pay the ticket? You could translate this in testing to a dataware house, which obtained incorrect data from the source. Should you as dataware house pay for the consequences or should the source pay for it by curing the symptoms. Perhaps we should as testers think beyond the rules and at a certain point look at the system as an open system, inflected by his environment. With regards, JeroenAnonymous
January 20, 2008
Hi Michael... just swinging by after neglecting to do so for a while. Anyway... this one was a chuckle... definitely a case of "For sale: antique table by old lady with wooden legs"! Why stop the interpretations at what the sign has written on it? One can interpret that some group made a policy, and some dept or company makes signs, and some crew had to install it... and after all that who knows if they even got the intended sign in the right spot... BTW: "EXCEPT-SUN" -- maybe that's a spelling mistake for "Exception" for HOLs :-) (and if think that's dopey, I actually live near a sign with a spelling mistake, and also one of those "BUMP" markers stencil-painted in 6 foot letters on the road, where the "M" is upside down!)Anonymous
January 21, 2008
Jeroen: Hooray to you for looking beyond my question and thinking about whether it needs to be answered at all!Anonymous
January 21, 2008
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January 23, 2008
Last week I asked you to see how many different interpretations of this sign you could devise. After