- URL:https://<geoanalytics-url>/FindSimilarLocations
- Version Introduced:10.5
Description
The FindSimilarLocations operation measures the similarity of candidate locations to one or more reference locations.
Based on criteria you specify, FindSimilarLocations can answer questions such as the following:
- Which of your stores are most similar to your top performers with regard to customer profiles?
- Based on characteristics of villages hardest hit by the disease, which other villages are high risk?
To answer questions such as these, you provide the reference locations (the inputLayer parameter), the candidate location (the searchLayer parameter), and the fields representing the criteria you want to match. For example, the inputLayer might be a layer containing your top performing stores or the villages hardest hit by the disease. The searchLayer contains your candidate locations to search. This might be all of your stores or all other villages. Finally, you supply a list of fields to use for measuring similarity. The FindSimilarLocations operation will rank all of the candidate locations by how closely they match your reference locations across all of the fields you have selected.
Request parameters
| Parameter | Details |
|---|---|
| inputLayer (Required) | The inputLayer contains one or more reference locations against which features in the searchLayer will be evaluated for similarity. For example, the inputLayer might contain your top performing stores or the villages hardest hit by a disease. For more information on inputLayer and searchLayer, see below. Syntax: As described in Feature input, this parameter can be one of the following:
REST Examples |
| searchLayer (Required) | The layer containing candidate locations that will be evaluated against the reference locations. For more information on inputLayer and searchLayer, see below. Syntax: As described in Feature input, this parameter can be one of the following:
REST Examples |
| analysisFields (Required) | A list of fields whose values are used to determine similarity. They must be numeric fields, and the fields must exist on both the inputLayer and the searchLayer. Depending on the matchMethod selected, the task will find features that are most similar based on values or profiles of the fields. REST Examples |
| mostOrLeastSimilar (Required) | The features you want to be returned. You can search for features that are either most similar or least similar to the inputLayer, or search both the most and least similar. Values: MostSimilar | LeastSimilar | Both REST Examples |
| matchMethod (Required) | The method that specifies how matching is determined. The AttributeValues method uses the squared differences of standardized values. This is the default. The AttributeProfiles method uses cosine similarity mathematics to compare the profile of standardized values. Using AttributeProfiles requires the use of at least two analysis fields. Values: AttributeValues | AttributeProfiles REST Examples |
| numberOfResults (Required) | The number of ranked candidate locations output to similarResultLayer. If numberOfResults is not set, the 10 locations will be returned. The maximum number of results is 10000. REST Examples |
| appendFields (Optional) | Add fields to your data from your search layer. By default, all fields from the search layer are appended. REST Examples |
| outputName (Required) | The task will create a feature service of the results. You define the name of the service. REST Examples |
| context (Optional) | The context parameter contains additional settings that affect task execution. For this task, there are four settings:
|
| f | The response format. The default response format is html. Values: html | json |
Notes on inputLayer and searchLayer
It is not uncommon for inputLayer and searchLayer to be the same feature service. For example, the feature service contains locations of all stores, one of which is your top performing store. If you want to rank the remaining stores from most to least similar to your top performing store, you can provide a filter for both inputLayer and searchLayer. The filter on inputLayer would select the top performing store, while the filter on searchLayer would select all stores except for the top performing store. You can use the optional filter parameter to specify reference locations.
If there is more than one reference location, similarity will be based on averages for the fields you specify in the analysisFields parameter. For example, if there are two reference locations and you are interested in matching population, the task will look for candidate locations in searchLayer with populations that are most like the average population for both reference locations. If the values for the reference locations are 100 and 102, for example, the task will look for candidate locations with populations near 101. Consequently, you will want to use fields for the reference locations fields that have similar values. If, for example, the population values for one reference location is 100 and the other is 100,000, the tool will look for candidate locations with population values near the average of those two values: 50,050. Notice that this averaged value is nothing like the population for either of the reference locations.
Example usage
Below is a sample request URL for FindSimilarLocations:
https://webadaptor.domain.com/server/rest/services/System/GeoAnalyticsTools/GPServer/FindHotSpots/submitJob?inputLayer={"url":"https://webadaptor.domain.com/server/rest/services/Hurricane/hurricaneTrack/0"}&searchLayer={"url":"https://webadaptor.domain.com/server/rest/services/Hosted/tornadoTrack/0"}&analysisFields=shelterLocations, shelterCapacity&mostOrLeastSimilar=MostSimilar&matchMethod=AttributeValues&numberOfResults=20&appendFields=&outputName=myOutput&context={"extent":{"xmin":-122.68,"ymin":45.53,"xmax":-122.45,"ymax":45.6,"spatialReference":{"wkid":4326}}}&f=jsonResponse
When you submit a request, the service assigns a unique job ID for the transaction.
{
"jobId": "<unique job identifier>",
"jobStatus": "<job status>"
}After the initial request is submitted, you can use jobId to periodically check the status of the job and messages as described in Check job status. Once the job has successfully completed, use jobId to retrieve the results. To track the status, you can make a request of the following form:
https://<analysis-url>/FindSimilarLocations/jobs/<jobId>Accessing results
When the status of the job request is esriJobSucceeded, you can access the results of the analysis by making a request of the following form:
https://<anaylsis-url>/FindSimilarLocations/jobs/<jobId>/results/<result type>?token=<your token>&f=json| Response | Description |
|---|---|
| output |
Contains features from the inputLayer and the searchLayer. The number of features from the searchLayer is based on the value of the numberOfResults parameter. Fields added to outputName include all the fields from the searchLayer and the following:
The result has properties for parameter name, data type, and value. The contents of value depend on the outputName parameter provided in the initial request. The value contains the URL of the feature service layer. See Feature output for more information about how the result layer is accessed. |
| processInfo | At 10.6.1 or later the processInfo parameter contains strings that summarize the Find Similar Locations result. These strings are used for reporting by the Find Similar Locations tool found in the map viewer. You can create your own custom reports for your application using these strings. There are four parts in the returned json:
|