Merge pull request #115 from cmu-delphi/develop/nowcast-docs

Update to 1.2.1 combination signal, and fix map table

Author: capnrefsmmat

docs/api/covidcast_signals.md

@@ -158,14 +158,22 @@ filtering, smoothing, or changes.
 This source provides signals which are statistical combinations of the other
 sources above. It is not a primary data source.
 
-* `nmf_day_doc_fbs_ght`: This signal uses a rank-1 approximation, from a
+* `nmf_day_doc_fbc_fbs_ght`: This signal uses a rank-1 approximation, from a
   nonnegative matrix factorization approach, to identify an underlying signal
-  that best reconstructs the Doctor Visits (`smoothed_cli`), Facebook Symptoms surveys (`smoothed_cli`), and Search Trends (`smoothed_search`)
-  indicators. It does not include official reports (cases and deaths from the
-  `jhu-csse` source). Higher values of the combined signal correspond to higher
-  values of the other indicators, but the scale (units) of the combination is
-  arbitrary. Note that the Search Trends source is not available at the county
-  level, so county values of this signal do not use it.
+  that best reconstructs the Doctor Visits (`smoothed_adj_cli`), Facebook
+  Symptoms surveys (`smoothed_cli`), Facebook Symptoms in Community surveys
+  (`smoothed_hh_cmnty_cli`), and Search Trends (`smoothed_search`) indicators.
+  It does not include official reports (cases and deaths from the `jhu-csse`
+  source). Higher values of the combined signal correspond to higher values of
+  the other indicators, but the scale (units) of the combination is arbitrary.
+  Note that the Search Trends source is not available at the county level, so
+  county values of this signal do not use it.
+* `nmf_day_doc_fbs_ght`: This signal is calculated in the same way as
+  `nmf_day_doc_fbc_fbs_ght`, but does *not* include the Symptoms in Community
+  survey signal, which was not available at the time this signal was introduced.
+  It also uses `smoothed_cli` from the `doctor-visits` source instead of
+  `smoothed_adj_cli`. This signal is deprecated and is no longer updated as of
+  May 28, 2020.
 
 ## COVIDcast Map Signals
 
@@ -175,8 +183,9 @@ map](https://covidcast.cmu.edu/):
 | Name | Source | Signal |
 | --- | --- | --- |
 | Doctor's Visits | `doctor-visits` | `smoothed_adj_cli` |
-| Surveys (Facebook) | `fb-survey` | `smoothed_cli` |
-| Surveys (Google) | `google-survey` | `smoothed_cli` |
+| Symptoms (Facebook) | `fb-survey` | `smoothed_cli` |
+| Symptoms in Community (Facebook) | `fb-survey` | `smoothed_hh_cmnty_cli` |
 | Search Trends (Google) | `ght` | `smoothed_search` |
+| Combined | `indicator-combination` | `nmf_day_doc_fbc_fbs_ght` |
 | Cases (JHU) | `jhu-csse` | `confirmed_incidence_prop` |
 | Deaths (JHU) | `jhu-csse` | `deaths_incidence_prop` |