All:

Geocoding problem solved, and many thanks to John Ottini of the Orlando
Public Works Dept., and to David Booth of Merseyside Information Service:

The vital change was to the layout of the map table (a mappable table of
street segments):   Per John Ottini,
Put the Street field and address range fields (FROMLEFT, TOLEFT, FROMRIGHT,
TORIGHT) at the extreme LEFT of the table.  All indexed, of course.
Geocoding didn't work when they were in the middle; did work when they were
at the left (beginning).
So that's the undocumented spec which has to be met!
This immediately yielded 178 hits on automatic geocoding.

The file to be geocoded carries addresses in ordinary US usage, house number
first; and this field  DOES NOT need to be the leftmost field.  Nor does it
need to be indexed (I reimported it and used it without indexing it; it
worked).

Mapinfow.abb was not part of my problem.  Nor was the option setting for
house number before street name (U.S. practice) vs. house number after
street name (German practice).
It appears, from looking at an example of a good table sent by David Booth
of Merseyside Information Service, that it is NOT necessary to have an
indexed unique identifier for the street segments immediately to the right
of those leading five.

David Booth also sent screen prints of the dialog boxes from a successful
geocoding operation.  This was very important to me personally, because I
could see what these looked like when the function was working.  
It turns out that in successful interactive geocoding, the street number
ranges will only be displayed where there is a choice of possible matches;
and the display is a little different from what I had expected.  Basically
the street number will be displayed without the street name next to them, in
that case.  (See John's email below for a written description).
I only wish Mapinfo's printed or Web documentation from Mapinfo showed these
pictures.

Now I am striking distance of my original plans. For those of you who are
curious, those are:
1) To compare people's home and work addresses in surveys, with bus stop
locations (in another map layer),
So as to have a check on the distance they say they walk to the bus.  (Or in
the case of non-riders, the distance they say they would have to walk to the
bus).  

Recognize that it's easy to ask people about distances, but the resulting
estimates are not reliable, which makes it hard to work with distances in
opinion or usage survey information: Respondents can count "blocks" but
blocks have many possible lengths in this town depending on who developed
the land.  They can say "minutes walk" but this implies different distances
for an octogenerian with a walker vs. a healthy twenty year old in a hurry.
They can say "miles" but some of those numbers don't have sight validity,
this term seems to be chosen by those who exaggerate.  "Yards"?  Any
distance estimation instructional exercise will show you that untrained
people are usually off by 25% or more in estimates of 100-300 yard
distances.  

Again, many thanks.

Ian Straus
Market Research Specialist
VIA Metropolitan Transit
San Antonio, Texas



From:   [EMAIL PROTECTED] [SMTP:[EMAIL PROTECTED]]
> Sent: Wednesday, April 18, 2001 10:40 AM
> To:   [EMAIL PROTECTED]
> Subject:      MI-L Geocoding: address ranges do not display
> 
> 
> Ian 
> 
> 
> Do the prescribed fields in Bexrdsl (Street, FromLeft, etc) have to be at
> the left of the table? 
> 
> Yes your (SEARCH TABLE) must be in order and starting at the left of the
> table- STREETNAME, FROMLEFT,TOLEFT, FROMRIGHT,TORIGHT etc. and these 5
> fields should all be Indexed (see Table/Maintainance/Table Structure) 
> 
> Do I have to separate the house number and the street name in the table to
> be geocoded (table WITR in my case)? 
> 
> No, leave the house numbers and streetname alone (ie 2345 John St is fine)
> 
> 
>  If so, what is the required format of
> that table?  (It must have some specific requirements since the dialog box
> for geocoding does not include an option to designate a house number
> field.) 
> 
> The FromLeft, ToLeft ,FromRight, ToRight, are the address range fields
> that Mapinfo will use to Geocode your WITR table. 
> 
> The mapinfow.abb file maybe part of your poor geocoding hit rate.If you
> have JAMES AVE and mapinfow.abb has AVENUE abbreviated as AV it will not
> locate the street in Automatic geocoding, but it should give you the
> option to varify the Street Name while using Interactive. The mapinfow.abb
> file can be modified if needed. 
> 
> Hope this helpful. 
> 
> John Ottini
> GIS Department
> City of Orlando-Public Works



Here is an example of what your layer should look like after Geocoding (see
Word file) 

Next is the Geocode option box that created what is in the Word file. If you
run this on Automatic Geocode you will not see the street address ranges. If
you run this in Interactive you will see the street ranges only when the
address you are searching for does not have a direct match (does not fall
within an address range in your SEARCH table) or you have 2 or more streets
with the same name in your SEARCH Table. Other than that you will not see
address ranges or address numbers when Geocoding. 

John Ottini
GIS Department
City of Orlando-Public Works


Ian Straus
Market Research Specialist
VIA Metropolitan Transit
San Antonio, Texas


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