Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: st: Choosing the best set of longitude/latitude coordinates from three choices
From
Eric Booth <[email protected]>
To
"<[email protected]>" <[email protected]>
Subject
Re: st: Choosing the best set of longitude/latitude coordinates from three choices
Date
Wed, 14 Jul 2010 16:29:33 +0000
<>
That's a good point. My example takes the minimum, not the minimum difference, so my loop in the previous post should be run on the absolute value of the differences that you calculated.
~ Eric
__
Eric A. Booth
Public Policy Research Institute
Texas A&M University
[email protected]
Office: +979.845.6754
On Jul 14, 2010, at 11:25 AM, Matthew Krauchunas wrote:
> Still messing around with this and I decided to take the absolute
> value of the differences to make it easier. Thus, the data now looks
> like this:
>
> oshpd_fac_no oshpd_lat oshpd_long usc_lat usc_long intel_lat intel_long oshpd_usc_lat_diff oshpd_usc_long_diff oshpd_intel_lat_diff oshpd_intel_long_diff intel_usc_lat_diff intel_usc_long_diff
> 206194113 34.22875 -118.3627 34.2298 -118.3629 34.2286 -118.3622 0.001053 0.000237 0.000145 0.000481 0.001198 0.000717
> 206194139 34.13254 -117.8698 34.13291 -117.8695 34.13241 -117.87 0.000370 0.000275 0.000130 0.000153 0.000500 0.000427
> 206194199 34.07075 -118.2026 34.07106 -118.2035 34.07067 -118.2026 0.000309 0.000870 0.000076 0.000015 0.000385 0.000854
> 206194202 34.69315 -118.157 34.69262 -118.1575 34.69285 -118.157 0.000534 0.000465 0.000298 0.000069 0.000237 0.000534
> 206194284 34.14379 -117.9671 34.14771 -117.9673 34.1431 -117.9675 0.003922 0.000198 0.000687 0.000435 0.004608 0.000237
> 206194320 34.03258 -118.3131 37.40501 -122.0915 37.40488 -122.0914 3.372433 3.778336 3.372299 3.778236 0.000134 0.000099
> 206194400 34.25798 -118.5727 34.25804 -118.5728 34.25835 -118.5725 0.000057 0.000031 0.000370 0.000252 0.000313 0.000282
> 206194558 34.28158 -118.4623 34.28167 -118.4608 34.28154 -118.4608 0.000095 0.001503 0.000042 0.001472 0.000137 0.000031
> 206194563 34.27824 -118.3992 34.28155 -118.4024 34.28153 -118.4026 0.003311 0.003250 0.003292 0.003410 0.000019 0.000160
>
>
> On Wed, Jul 14, 2010 at 11:19 AM, Matthew Krauchunas
> <[email protected]> wrote:
>> Hello,
>>
>> The data management process for my dissertation is fraught with
>> obstacles beyond my current Stata abilities, so I am returning to the
>> "well" where everyone has been extremely helpful.
>>
>> I have some geocoded data from three sources and I need to figure out
>> a way to choose the best set of coordinates. The source of the
>> coordinates are Intelligentsearch GIS (intel_lat & intel_long), USC
>> GIS (usc_lat & usc_long), and OSHPD provided GIS (oshpd_lat &
>> oshpd_long). The OSHPD GIS also has 71 missing longitudes and
>> latitudes. I have calculated the difference between these three sets
>> of coordinates: Intelligentsearch & USC
>> (intel_usc_lat_diff intel_usc_long_diff), OSHPD & USC
>> (oshpd_usc_lat_diff oshpd_usc_long_diff), and OSHPD &
>> Intelligentsearch (oshpd_intel_lat_diff oshpd_intel_long_diff). I
>> need to keep the best coordinates (i.e., from two datasources with the
>> smallest difference), name the new coordinates longitude and latitude,
>> and use the USC coordinates as the default (i.e., use the USC
>> coordinates when the smallest difference is between USC and
>> Intelligentsearch).
>>
>> Let me provide an example: oshpd_fac_no 206194320 has a
>> oshpd_usc_lat_diff of -3.372433, oshpd_intel_lat_diff of -3.372299,
>> and a intel_usc_lat_diff of 0.000134. Obviously the OSHPD gis is the
>> problem and the USC latitude needs to be kept as it is my default.
>>
>> Does anyone have any ideas for this?
>>
>> Here is some sample data if it helps:
>>
>> oshpd_fac_no intel_usc_lat_diff intel_usc_long_diff oshpd_usc_lat_diff oshpd_usc_long_diff oshpd_intel_lat_diff oshpd_intel_long_diff oshpd_long oshpd_lat usc_lat usc_long intel_lat intel_long
>> 206271717 -2.928555 4.037598 2.928555 -4.037582 0.000000 0.000015 -121.9128 36.56206 33.63351 -117.8752 36.56206 -121.9128
>> 206100833 -0.124664 0.399834 0.123066 -0.401627 -0.001598 -0.001793 -119.4988 37.10662 36.98355 -119.0972 37.10822 -119.497
>> 206491017 -0.086819 0.052116 0.024086 -0.007385 -0.062733 0.044731 -122.4599 38.27798 38.25389 -122.4525 38.34071 -122.5046
>> 206044001 -0.058876 -0.041939 0.058018 0.040482 -0.000858 -0.001457 -121.598 39.78528 39.72726 -121.6385 39.78614 -121.5965
>> 206190123 -0.056854 -0.162796 0.054424 0.182648 -0.002430 0.019852 -118.2801 34.05378 33.99936 -118.4627 34.05621 -118.2999
>> 206281040 -0.050270 -0.041695 0.000572 0.000282 -0.049698 -0.041412 -122.3058 38.31432 38.31374 -122.3061 38.36401 -122.2644
>> 206040974 -0.039154 -0.023483 0.043438 0.026169 0.004284 0.002686 -121.6123 39.7707 39.72726 -121.6385 39.76641 -121.615
>> 206070948 -0.038231 -0.044518 -0.001057 -0.000832 -0.039288 -0.045349 -122.132 37.88853 37.88959 -122.1312 37.92782 -122.0867
>> 206374019 -0.036625 -0.008965 -0.001068 -0.000153 -0.037693 -0.009117 -116.984 32.83546 32.83652 -116.9839 32.87315 -116.9749
>> 206301202 -0.033604 -0.016846 -0.000050 -0.001251 -0.033653 -0.018097 -117.836 33.74546 33.74551 -117.8347 33.77912 -117.8179
>> *
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/