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-rw-r--r--docs/cpta/methodology/index.rst50
1 files changed, 25 insertions, 25 deletions
diff --git a/docs/cpta/methodology/index.rst b/docs/cpta/methodology/index.rst
index 35c438d8b6..d89a6d7aed 100644
--- a/docs/cpta/methodology/index.rst
+++ b/docs/cpta/methodology/index.rst
@@ -94,16 +94,16 @@ over the rolling window of last <N> sets of historical measurement data:
Outlier Detection
`````````````````
-Outlier evaluation of test result of value :math:`X_n` follows the
-definition from previous section:
+Outlier evaluation of test result of value *X* follows the definition
+from previous section:
-+--------------------------------------------+----------------------+
-| Outlier Evaluation Formula | Evaluation Result |
-+============================================+======================+
-| :math:`X_n < \left( Q1 - 1.5 IQR \right)` | Outlier |
-+--------------------------------------------+----------------------+
-| :math:`X_n >= \left( Q1 - 1.5 IQR \right)` | Valid (For Trending) |
-+--------------------------------------------+----------------------+
++----------------------------+----------------------+
+| Outlier Evaluation Formula | Evaluation Result |
++============================+======================+
+| X < (Q1 - 1.5 * IQR) | Outlier |
++----------------------------+----------------------+
+| X >= (Q1 - 1.5 * IQR) | Valid (For Trending) |
++----------------------------+----------------------+
Anomaly Detection
`````````````````
@@ -112,15 +112,15 @@ To verify compliance of test result of valid value <X> against defined
trend metrics and detect anomalies, three simple evaluation formulas are
used:
-+---------------------------------------------------------------------------+-----------------------------+-------------------+
-| Anomaly Evaluation Formula | Compliance Confidence Level | Evaluation Result |
-+===========================================================================+=============================+===================+
-| :math:`\left( TMM - 3 TMSD \right) <= X_n <= \left( TMM + 3 TMSD \right)` | 99.73% | Normal |
-+---------------------------------------------------------------------------+-----------------------------+-------------------+
-| :math:`X_n < \left( TMM - 3 TMSD \right)` | Anomaly | Regression |
-+---------------------------------------------------------------------------+-----------------------------+-------------------+
-| :math:`X_n > \left( TMM + 3 TMSD \right)` | Anomaly | Progression |
-+---------------------------------------------------------------------------+-----------------------------+-------------------+
++-------------------------------------------+-----------------------------+-------------------+
+| Anomaly Evaluation Formula | Compliance Confidence Level | Evaluation Result |
++===========================================+=============================+===================+
+| (TMM - 3 * TMSD) <= X <= (TMM + 3 * TMSD) | 99.73% | Normal |
++-------------------------------------------+-----------------------------+-------------------+
+| X < (TMM - 3 * TMSD) | Anomaly | Regression |
++-------------------------------------------+-----------------------------+-------------------+
+| X > (TMM + 3 * TMSD) | Anomaly | Progression |
++-------------------------------------------+-----------------------------+-------------------+
TMM is used for the central trend reference point instead of TMA as it
is more robust to anomalies.
@@ -135,13 +135,13 @@ ago, TMM[last - 1week] and to the maximum of trend values over last
quarter except last week, max(TMM[(last - 3mths)..(last - 1week)]),
respectively. This results in following trend compliance calculations:
-+-------------------------+---------------------------------------------+--------------------------------+------------------------------------------------------------------------------------------------------------+
-| Trend Compliance Metric | Change Formula | Value | Reference |
-+=========================+=============================================+================================+============================================================================================================+
-| Short-Term Change | :math:`\frac{Value - Reference}{Reference}` | :math:`TMM \left[ last \right] | :math:`TMM \left[ last - 1 week \right]` |
-+-------------------------+---------------------------------------------+--------------------------------+------------------------------------------------------------------------------------------------------------+
-| Long-Term Change | :math:`\frac{Value - Reference}{Reference}` | :math:`TMM \left[ last \right] | :math:`max \left( TMM \left[ \left( last - 3 mths \right) .. \left( last - 1 week \right) \right] \right)` |
-+-------------------------+---------------------------------------------+--------------------------------+------------------------------------------------------------------------------------------------------------+
++-------------------------+---------------------------------+-----------+------------------------------------------+
+| Trend Compliance Metric | Trend Change Formula | Value | Reference |
++=========================+=================================+===========+==========================================+
+| Short-Term Change | (Value - Reference) / Reference | TMM[last] | TMM[last - 1week] |
++-------------------------+---------------------------------+-----------+------------------------------------------+
+| Long-Term Change | (Value - Reference) / Reference | TMM[last] | max(TMM[(last - 3mths)..(last - 1week)]) |
++-------------------------+---------------------------------+-----------+------------------------------------------+
Trend Presentation
------------------