GPSIreland Postcode ideas

Posted: March 20th, 2008 | Author: antoin | 5 Comments »

I’ve written loads about postcodes before. GPS Ireland have published a concept for a postcode system, and Garmin have implemented it in a limited way on their devices. Good for them for publishing their idea.
However, there are a number of big issues with implementing such a system.

- The problem is that it is not much help in and of itself to actually deliver anything, except maybe by helicopter. You need to cross-reference the code against a map database to have any idea of how to effect the delivery or to estimate how long the delivery might take. This means that you are in a proprietary situation right away. There is no free road map database of Ireland.
- Packets and parcels with the code (and packets and parcels will represent 80 percent of delivery items within 20 years) would be practically impossible to sort by hand. You have to key ‘em or scan ‘em to have any idea which bag to put them in. Manual sorting of letters by unskilled workers is still a reality of the Irish postal system at the busiest times. Many other items (like registered letters and packages) are also manually sorted.

- You can have very ambiguous codes. For example, if you have a short back garden, you could end up with a code the same as the guy in the house backing on to you. In some cases, it could be a one-mile drive to the other property.

- The resolution of the system is just not that high for central areas. It’s only 5m. A significant number of houses in Ireland are smaller than 5m on one or other dimension.

- You really need a centralized database of addresses to do most useful tasks with the code (for example, verifying an address as valid). Sorting out this national address database is the big challenge for any postcode implementation. To do the surveys required from scratch for this system would cost at least EUR 15m, and maybe more.

- Google maps is just not an accurate way of determining longitude and lattitude. It is often many inaccurate by tens or even hundreds of metres, because of the way the projections work.

- letters in codes are not a good idea. They make it more likely that the code will be misremembered, misheard or misread. Letters that look alike, or like numbers, such as  ‘S’, ‘Z’ and letters that sound alike, such as ‘N’ and ‘M’ in particular are going to cause confusion and errors.

My own suggestion, which I have worked on with Michael Everson, is to use an all-numbers 5+4 code and base the code on existing administrative divisions, subdividing to road/street and individual delivery point level as necessary, and to number the codes geographically, i.e, the district in the top left of a county is numbered 101 and the district in the bottom right is number 909.

This has the following advantages:
- keeps the implementation costs to a minimum at the outset

- allows items to be be easily sorted manually or by machine

- can be implemented in a basic way without any proprietary databases (although it can conveniently link to proprietary databases)
- integrates well with existing databases (like census, rates office, electoral register and geodirectory)
- does not absolutely require a single address database at the outset (although one may have to be constructed over time on the basis of existing databases)

- allows the system to be extended where necessary (subdivision to provide a unique address for each home is not a big issue in Dublin City for example, but it is a big issue in some rural areas and is more likely to be cost-effective there).
- can cope with certain areas of the country becoming much higher density over time

- makes it obvious for a non-specialist withough special equipment as to where in the country a particular address is located.

This scheme isn’t perfect either of course, but after talking to a lot of people and considering a lot of options, it seems like the best way to do it. We also have a plan for giving the postcode legal backing, without requiring an Act of the Oireachtas.


5 Comments on “GPSIreland Postcode ideas”

  1. 1 Gary Delaney said at 10:42 pm on March 20th, 2008:

    Reply By Gary Delaney – GPS Ireland – Developer of the PON Codes
    Antoin’s detailed discussion on our PON Code (Position Orientated Navigation) Code, or Post Code for popular understanding, deserves my detailed response. It should be noted by readers that essentially here we have two competing ideas – so you can expect that we will disagree on most elements and it is up to potential users to decide which is better.
    Essentially however, talking about an idea and making it a reality are two different things. Our solution is passed idea stage and was easily implemented by Garmin for testing. See here http://www.gpsireland.ie/index.php?option=com_content&task=view&id=47&Itemid=79
    Antoin probably does not understand our system well enough judging from the comments he has made – so it is best that I respond directly to each issue he raises. His comments are shown in Square brackets and my reply follows – all below:
    [Antoin: The problem is that it is not much help in and of itself to actually deliver anything, except maybe by helicopter. You need to cross-reference the code against a map database to have any idea of how to effect the delivery or to estimate how long the delivery might take. This means that you are in a proprietary situation right away. There is no free road map database of Ireland]. Gary: These comments are misleading – Antoin is already aware that there are two possibilities with any Post Code or adressing system to find distance – 1. without maps you can only calculate as-the-crow-flies distances and this is not much use to any Post or Logistics manager and 2. To find true distances along roads the user has to have access to digital road mapping, there is no escaping this no matter what means of identifying address you use. This is the same with Antoin’s proposed system. Our proposed system has the advantage that it is already geographic and option 1. can be done without any lookup database and with even the most basic SatNav systems or related software costing as little as Euro 240, option 2 can be calculated.
    [Antoin: Packets and parcels with the code (and packets and parcels will represent 80 percent of delivery items within 20 years) would be practically impossible to sort by hand. You have to key ‘em or scan ‘em to have any idea which bag to put them in. Manual sorting of letters by unskilled workers is still a reality of the Irish postal system at the busiest times]. Gary: This is also not true – each character on our code represents a geographic area and a simple map on a wall can be consulted to help sort the mail. See the sample map at this link – see here: http://www.gpsireland.ie/images/GPSIPonCodes/gpsi%20pon%20code%20example.pdf – showing area “W” which is a 100km square covering most of Cork. The first 3 characters of our code defines which of the lettered areas the address is in. This is not unlike Antoin’s proposal except that we need only 7 characters and we have gone one step further and made then directly related to geographic coordinates which any developers or manufacturer’s mapping software and SatNav’s can readily understand because they all handle Latitude and Longitude already as a minimum. There are several 100km square areas covering all of the island of Ireland.
    [Antoin: You can have very ambiguous codes. For example, if you have a short back garden, you could end up with a code the same as the guy in the house backing on to you. In some cases, it could be a one-mile drive to the other property] Gary: Any Lat & Long or Grid coordinate can be converted into a PON Code and every millimeter of ground in Ireland is defined by Lat &Long or ITM grid. We allow 5 meter accuracy for the accuracy of mapping or positioning systems used commercially. Our system also facilitates the use of house number or property name and indeed floor number to facilitate the final 5 meters to enter the building and climb the stairs if necessary. See this link for details of this aspect of the code> It should also be stated that nothing could ever be delivered on the basis of a Post Code only – as is normal, full addresses would also be on Packages and delivery slips for final visual recognition. This will only change when we are using “Beam Me Up Scotty” techniques – so there is a need for realism in the argument here.
    [Antoin: You really need a centralized database of addresses to do most useful tasks with the code (for example, verifying an address as valid). Sorting out this national address database is the big challenge for any postcode implementation. To do the surveys required from scratch for this system would cost at least EUR 15m, and maybe more]. Gary: Yes every traditional Post Code system in existence or proposed needs a geographic data base except ours. Antoin’s system, as well as traditional Post Code systems, give a code to a structure and then require the user or software to look up a database to see what the geographic coordinates are. Ours does not as the Code used has a mathematical relationship to the geographic coordinates and therefore instead of using an expensive database which takes time and money to create and maintain, all is required is the formula to covert the code to coordinates – so simple that Garmin were able to do this straight away and all mapping and Satnav manufactures can do this in several lines of code because they are already handling Latitude and Longitude as a minimum. As for checking addresses – well these are already in SatNav’s and desktop software associated with SatNav’s and when our system is fully deployed after the PON code is entered it will return the address as a gross error check for the user in case an error has been made. Such software or SatNav’s cost as little as Euro 240 for all of Europe Mapping!!! So no mapping to be done and no database to be created!
    [Antoin:Google maps is just not an accurate way of determining longitude and lattitude. It is often many inaccurate by tens or even hundreds of metres, because of the way the projections work]. Gary: There is no reference in anytime published on our system to Google mapping, however as it is referred to here I will deal with the issue. There are numerous web mapping programmes available for free use. There have been some errors in the ground truthing of the Satellite image data used in these, although this has been reduced of late. However, the road mapping and address details used in these Web Services is the same as in SatNav systems with only meters of error – which is normal for any mapping, including the Ordnance Survey of Ireland data. Most people will be aware that there is now almost 100% coverage of Ireland in this type of mapping. However because there is still lots of construction;- new roads and new structures, if using our system there will no need to wait until it is surveyed by the Ordnance Survey or put on Web Maps – our code will function even if there is nothing on the map. In fact this is what makes it most attractive and flexible – traditional Post Code systems only work for existing buildings – but what if I want to send a parcel to a mobile clinic, deliver cement to an office block under construction, deliver grain to a silo or bring a horse to a Point To Point meeting – using PON codes this can be done too and by the user – no need to wait months for someone else to do a survey and supply a Post Code – a modern solution for modern needs!!!
    [Antoin: letters in codes are not a good idea. They make it more likely that the code will be misremembered, misheard or misread. Letters that look alike, or like numbers, such as ‘S’, ‘Z’ and letters that sound alike, such as ‘N’ and ‘M’ in particular are going to cause confusion and errors]. Gary: The Gardai don’t seem to have any problems reading letters on car registration number plates! I am not sure that anyone has ever had a problem finding “SW1” when looking for Buckingham Palace either! However, just to help, our System has removed certain letters and numbers in certain places. And to remove the possibility of gross errors, on a SatNav when fully implemented, once a PON Code is entered the system will return an address for cross checking. So no fears there either!
    [Antoin:My own suggestion, which I have worked on with Michael Everson, is to use an all-numbers 5+4 code and base the code on existing administrative divisions, subdividing to road/street and individual delivery point level as necessary, and to number the codes geographically, i.e, the district in the top left of a county is numbered 101 and the district in the bottom right is number 909.] Gary: Antoin is proposing to use 9 numbers – that is more than a telephone number – nobody remembers phone numbers anymore – they use their Mobile phones for that! Using administrative divisions as a starting point is dangerous as these can change and also require a database to define their location and extent. Relating codes to roads is the traditional approach but what happens when new roads, housing estates and business parks are added? Whilst Antoin’s codes may be numbered geographically, they have no relationship to geographic coordinates and another element in a database will be required for this. Don’t forget that databases have to be made and maintained at a cost!
    [Antoin: keeps the implementation costs to a minimum at the outset] Gary: But the geographic location of a property must still be defined and where does this come from – is it the Geodirectory? This is a database which must be paid for and maintained and only contains buildings (indeed not all buildings!) – not carparks, sports grounds, ATM machines, Speed cameras, mobile clinics, building sites, accident locations etc all of which we may want to get to or deliver to. The Geodirectory was already sited as unsuitable for Post Coding by Noel Dempsey in his statement in the Dail in June 2005 – extract given below….
    [Antoin: allows items to be be easily sorted manually or by machine] Gary: in the same way any Post Code including the PON Code does – not a unique feature in any way!
    [Antoin: can be implemented in a basic way without any proprietary databases (although it can conveniently link to proprietary databases)] Gary: Needs a geographic coordinates database as a minimum and must be manually related to it otherwise it has no value!
    [Antoin: integrates well with existing databases (like census, rates office, electoral register and geodirectory)] Gary: Any database can integrate with any other database on a computer. In the end, no matter how it works, geographic coordinates must be added to Antoin’s coding system – not with PON Codes;- they are one and the same thing!
    [Antoin: does not absolutely require a single address database at the outset (although one may have to be constructed over time on the basis of existing databases)] Gary: PON Codes do not require any database – they are geographic codes which are only seven characters long and easily remembered – GPS Ireland’s PON Code is WVR J3DQ – and WVR covers all of Crosshaven and Ringaskiddy in Cork – simple!
    [Antoin:This scheme isn’t perfect either of course, but after talking to a lot of people and considering a lot of options, it seems like the best way to do it. We also have a plan for giving the postcode legal backing, without requiring an Act of the Oireachtas.] Antoin I like your system but it only goes some of the way and has been conceived with only delivering mail in mind. You say yourself that “and packets and parcels will represent 80 percent of delivery items within 20 years” as well as cement and carpets and fridges and beds and bicycles and bales of hay and tourists and, indeed, services provided by people (service engineers etc);- all of which must first travel by vehicle. So the system we implement must satisfy these requirements also. This debate unfortunately has been distracted by the term “Post Code” i.e. The requirement to deliver Post (mail) – modern requirements dictate a fresh approach;- one which understands that all of this is about Navigation. Every human being navigates in their daily lives and in recent years over a million people in Ireland have chosen to use SatNav’s, GPS and Digital Mapping to help them with their daily navigation tasks. Since Nokia has recently spent US$8Billion on Digital Mapping to add to the GPS in their phones, it is clear that GPS will be used by every mobile phone user in the next 10 years. In these systems Grid references and Latitude and Longitudes are used as a matter of course. PON Codes are Grid references and Latitude and Longitudes in a more useable form and so they will be eventually used by the whole population. It would be only a small few that would have a need for traditional Post Code systems and these would include Direct Marketing companies who like the database approach!. Finally, regarding “legal backing”, Grid References and Latitudes and Longitudes have been used since the days of the explorers and are already widely used by over one quarter of our population, so PON Codes do not even need the local sergeant’s backing to use them!!

    I hope I have calrified matters – if not plaese feel free to contact me and we are currently looking for anyone with commercial vehicles on the road to help with the field testing – gary@gpsireland.ie Tel: 021 4832990 – http://www.gpsireland.ie

    Dail Eireann Extract referring to The GeoDirectory:…………….
    Dáil Éireann – Volume 605 – 29 June, 2005
    Written Answers – Postal Services.
    Mr. English Mr. English
    229. Mr. English asked the Minister for Communications, Marine and Natural Resources the reason the existing GeoDirectory system, that contains each of the 1.5 million building records in the State, cannot be utilised by An Post rather than the proposed postal code system; and if he will make a statement on the matter. [23197/05]
    Mr. N. Dempsey Mr. N. Dempsey
    Mr. N. Dempsey: I have asked the Commission for Communications Regulation, ComReg, to appoint project managers to support the postcode project. As a next step I will appoint a national postcode project board, comprising representatives of Departments together with public and private sector organisations, to assist the project managers with their work. It is hoped to present a proposal describing in sufficient detail the most efficient, effective and most publicly usable postcode system by 31 December 2005. In its deliberations, the project board will examine all of the options for a postcode system. This may include an examination of An Post’s GeoDirectory.
    Whilst the GeoDirectory has already been developed and adopted by some organisations and goes some way towards solving the problem of identifying individual addresses in townlands, it has certain characteristics that impact upon its suitability for use as a public postcode system and it is not consistent with the generally accepted definition of a postcode as a “unique, universal identifier that unambiguously identifies the addressee’s locality and assists in the transmission and sorting of mail items.”
    1335
    [1335] An Post has also advised that the GeoDirectory product is not a publicly available postcode system. It is a commercial, proprietary, address database that is linked to geographical co-ordinates to provide a unique identifier for buildings and has been developed by An Post and Ordnance Survey Ireland. The cost of the GeoDirectory product supplied by An Post is expensive for most businesses and comprises a once-off fee of €57,000 plus an annual licensing fee of 14% of the initial cost. These high costs reflect that keeping the GeoDirectory database updated is a continual and labour intensive exercise and that geo codes are not automatically assigned and require manual intervention.
    While a postcode can be used with automated mail process systems, it must also be capable of being used with manual systems. The GeoDirectory product is a building identifier and the purpose of a postcode system is to make it easier to process and deliver mail. The GeoDirectory’s design means that it is only when combined with An Post sorting technology that it can be employed as a technical postcode. However, because approximately 40% of Irish addresses are not “unique”, the An Post sorting technology, when deployed, cannot always match the address written on the envelope with the list of delivery points. If a postcode system were in place a much greater proportion of letters could be automatically sorted, and when human intervention is necessary the time needed would be shorter.
    Other potential drawbacks to the use of the GeoDirectory as a postcode system, as identified by ComReg, include that there may also be data protection and privacy issues as the database requires an occupier’s name to be recorded on the database in rural areas. It is also a sequential technical code that is not intuitive or easy to recall and this could impact upon the public adoption rates of any new postcode system based on the GeoDirectory.

  2. 2 Gary Delaney said at 7:04 am on March 21st, 2008:

    Antoin,

    be fair – you cannot publish a criticism of my system and then conveniently censor my reply and defense. Are you going to publish it?

    Gary

  3. 3 Gary Delaney said at 7:05 am on March 21st, 2008:

    Sorry – last post not necessary Gary

  4. 4 Gary Delaney said at 10:03 am on March 23rd, 2008:

    Are you going to post this???

  5. 5 Administrator said at 9:12 am on March 27th, 2008:

    A few quick responses. Firstly, my post is just that, a post. It’s not an ‘official’ response or anything like that. It’s just some views.
    I think it would be unwise to roll out a code without some form of statutory backing. It can cause a lot of issues later on, when changes need to be made and you need to bring everyone along with you. There is already a big problem here in Ireland with standardization for addresses. Legal addresses for example, are now very much at odds with postal addresses in many parts of the country. This is a crazy situation.

    I’m glad you like our system! Our system isn’t particularly conceived with mail in mind. It doesn’t use mail delivery areas for instance.

    Letters and numbers. Using letters in a postcode is just a bad idea which causes confusion in writing and on the phone. There are many issues with reading even registration plates, even though the letters are standardized. There is no evidence other than anecdotal showing that having letters aids recall. There is plenty of evidence of slips as a result of using alphanumeric codes. There is fairly well established best practice on this at this stage.

    This is a key issue, because it determines how much infomation you can fit into 7 or so characters. The ponc system depends on fitting an awful lot of infomation in there.

    Address Database. It is hard to avoid having a national address database. There is not necssarily any incremental maintenance cost to doing this, since the State alone maintains a number of address databases, all of which have particular problems which have to be resolved in any case. A single address database would not cost anything extra to maintain over and above what is already being spent.

    The GPS device manufacturers buy in this database. Again, there is cost here. Having multiple address databases is just not a great idea. There should be one address database.

    Sortability. What you are describing is a tough way to sort mail. It basically means that there is no relationship between the street address and the postcode. The mail has to be ultimately sorted for delivery on the basis of the street address rather than on the basis of the code. As a result, Irish addresses becomes even less hierarchical than it was before. (I accept that you could do a certain amount of sorting this way.)

    Uniqueness of codes. I think that every delivery point should have one and only one code. You don’t. We could have a long discussion about this.

    Survey. What you are proposing would require re-surveying from scratch in order to get started. It does not really matter whether this surveying is done by individuals or companies or the government. It is still a substantial cost. You don’t think a national  door-to-door survey is required to assign postcodes, but from what you describe, my view is that it would in fact be needed to ensure the high level of accuracy required and to ensure all the various features of the code are properly applied.

    Updates. You always have to do updates with any system to keep the database up to date. Occasionally our system requires renumbering, but the numbers are arranged so that renumbering is rare, and numbers are never reused.

    Roll-out. How would the code be applied to existing mail, i.e., how would eircom or ESB apply the code to their database? I think this would be very difficult.

    However, it is designed around human settlements and the core communications infrastructure (i.e., the roads network). It reflects the roads network.

    As a result of that, incidentally, it would be possible in principle to take the completed postcode system, according to our model, and plot meaningful routes, based on the information in the postcode database alone.

    Integrating a system like this with GPS would be very straightforward, and would just be an adjunct to the existing address database. The address database itself would probably be free.

    On the length of our code – 5+4 seems workable. 5 digits is what people would normally use, and the additional 4 digits would mostly be used internally and in computer systems, similar to the situation in the US, but it might also be useful to make rural addresses unique.

    You wouldn’t necessarily need to break down the whole country beyond 5 digits. It would still be a highly useful code.

    I have just skimmed the response on your website which includes some extra information beside your comment above.

    http://www.gpsireland.ie/images/stories/PostCodes/gpsi%20blog%20replies.pdf

    I would be interested to see good evidence that the human being is best at remembering no more than 7 characters, or indeed that the human body replaces itself every seven years.

    I was looking for details of how your code is calculated. I can see where the first few digits come from but where can I find details for the rest?


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