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I am relatively new to GIS and am facing some difficulties trying to summarize/pool data together.

I've attached the file to make it easier. FID_pc11_1 (Refers to postcode identifier) and count refers to the number of each postcode. Basically, there are 2107 objectid_1 (which is the different buffer zones around schools), code represents the different lower super output areas in UK.

I would like to summarize my data, such that it would give me data in the format of; in zone 1 (eg.objectid_1= 1),what is the summated count (of postcodes) for each of the code/lower super output layer (eg:E101002711).

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  • I'm interpreting your question a little differently than @MichaelMiles-Stimson is - you may wish to edit and clarify by providing a clearer example of the output you want. – Chris W Jun 19 '14 at 7:23
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The summary statistics tool will do what you want.

Specify postcode as case field and summary field with a statistic of type count. This will give you a table with each unique postcode and then a count of how many instances appear in the table.

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I'm interpreting that you want a count of postcodes in each code per zone:

Zone 1, 2711, 4; Zone 1, 2728, 1; Zone 1, 0938, 2; etc.

Using Michael's solution of Summary Statistics you would add zone as your first case field and code as your second. You don't need a statistics field to get the count you want since code will occur the same number of times each postcode does. With a case field it automatically creates a Frequency field in the resulting table that counts the occurences of each case or unique combination if multiple cases. But since you have to specify a statistics field for the tool to run you could do postcode using count. You'll end up with two identical value fields - Frequency and postcode count.

As an alternative to Summary Statistics, you can use the Frequency tool if you have an Advanced/Info license. There you would just check the zone and code fields and it will generate the same Frequency field for each unique combination of zone and code and the number of times it occurs.

Another alternative would be to export your table and perform the frequency analysis in Excel or similar spreadsheet program. Could probably be done in database software with SQL too.

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    I think you can also do this using the Summary Statistics (Analysis) with two case fields, which only needs a Basic level license. – PolyGeo Jun 18 '14 at 23:54
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    Yes, summary statistics can have more than one case field. I like the Excel idea too @chrisw. Many times I have opened a dbf file and done a pivot table to get the statistics that I actually need. – Michael Stimson Jun 18 '14 at 23:59
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    @PolyGeo You're both absolutely right. When I was being taught about those tools I was told you had to use Frequency if you wanted multiple case fields. Or maybe I was just confused that you can't do that with Summarize (which is true). Corrected either way and good to know! Kind of makes you wonder what the point of Frequency and being restricted to Advanced is though. – Chris W Jun 19 '14 at 7:26
  • @ChrisW It's historical - ARC/INFO which became ArcInfo Workstation had a tool called FREQUENCY so when the ArcGIS Desktop architecture came along ArcInfo (which became Advanced) level license users expected to find a similar tool. Summary Statistics is the superior tool of the two. +1 for your now comprehensive Answer. – PolyGeo Jun 19 '14 at 7:32

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