Exploring Outliers and Contributing Drivers - Amazon QuickSight

Exploring Outliers and Contributing Drivers

You can interactively explore the anomalies (also known as outliers) in your analysis, along with the contributors (key drivers). The exploratory analysis is available after ML-powered anomaly detection runs. The changes you make in this screen aren't saved when you go back to the analysis.

To begin, choose Explore anomalies at the lower left of the insight widget. The following screenshot shows the anomaly exploration screen with numbered sections, which correspond to the descriptions the follow the screenshot.

The four sections of the screen include the following:

  1. Anomaly exploration

  2. Sheet controls

  3. Anomalies by date

  4. Contributors

Screen section 1: Exploring anomalies (outliers) – The main section of the Explore anomalies screen, which is always displayed when the screen opens. Anchored to the lower right of the screen, it remains on the lower right no matter how many other sections of the screen are open.

The Exploring anomalies main section, shown preceding, contains the following components:

  • Configure alerts – If you are exploring anomalies from a dashboard, you can use this button to subscribe to alerts and contribution analysis (if it's configured). You can set up the alerts for the level of severity (medium, high, and so on). You can get the top five alerts for Higher than expected, Lower than expected, or ALL. Dashboard readers can configure alerts for themselves. The Explore Anomalies page doesn't display this button if you opened the page from an analysis.

    Note

    The ability to configure alerts is available only in published dashboards.

  • Status – Under the Anomalies header, the status label displays information on the last run, for example "Anomalies for Revenue on November 17, 2018." This label tells you how many metrics were processed and how long ago. You can choose the link to learn more about the details, for example how many metrics were ignored.

Screen section 2: Sheet controls for exploring anomalies – Expand this section, shown preceding, by choosing the down arrows on the far right of the Controls shelf. This section contains the following:

  • Controls – The current settings display at the top of the workspace. You can expand this by using the double arrow icon on the far right. The following settings are available for exploring outliers generated by ML-powered anomaly detection:

    • Anomaly threshold – Sets how sensitive your detector is to detected anomalies (outliers). You should expect to see more anomalies with the threshold set to Low, and fewer anomalies when the threshold is set to High. This sensitivity is determined based on standard deviations of the anomaly score generated by the RCF algorithm.

    • Anomaly direction – Sets the display to show anomalies that are either higher or lower than expected.

    • Sorting method – Choose the method that you want to apply to sorting anomalies. These are listed in preferred order on the screen. Here they are listed alphabetically:

      • Weighted anomaly score – The anomaly score multiplied by the log of the absolute value of the difference between the actual value and the expected value. This score is always a positive number.

      • Anomaly score – The actual anomaly score assigned to this data point.

      • Weighted difference from expected value – (Default) The anomaly score multiplied by the difference between the actual value and the expected value.

      • Difference from expected value – The actual difference between the actual value and the expected value (actual−expected).

      • Actual value – The actual value with no formula applied.

    • Categories – One or more category settings appear at right, based on the fields in the category field well. Using these settings, you can limit the data that displays in the screen.

Screen section 3: Anomalies by date – To explore anomalies (outliers) for the most recent data point in the time series, choose SHOW ANOMALIES BY DATE. A new section, shown preceding, expands to display the following components:

  • Anomalies – The center of the screen displays the anomalies for the most recent data point in the time series. One or more graphs display with a chart showing variations in a metric over time. To use this graph, you select a point along the time line. The currently selected point in time is highlighted in the graph, and has a context menu offering you the option to analyze contributions to the current metric. You can also drag the cursor over the time line without choosing a specific point, to display the metric value for that point in time.

  • Anomalies by date – If you choose SHOW ANOMALIES BY DATE, another graph appears that shows how many significant anomalies there were for each time point. You can see details in this chart on each bar's context menu.

  • Timeline adjustment – Each graph has a timeline adjustor tool below the dates, which you can use to compress, expand, or choose a period of time to view.

Screen section 4: Contributors (drivers) – The left side of the screen displays drivers that are contributing to the anomalies, as shown preceding. It has the following components:

  • Narrative – At top left, a narrative displays to describe any change in the metrics.

  • Top contributors configuration – Choose Configure to change the contributors and the date range to use in this section.

  • Sort by – Sets the sort applied to the results that display below. You can choose from the following:

    • Absolute difference

    • Contribution percentage (default)

    • Deviation from expected

    • Percentage difference

  • Top contributor results – Displays the results of the top contributor analysis for the point in time selected on the timeline at right.

    Contribution analysis identifies up to four of the topmost contributing factors or key drivers of an anomaly. For example, Amazon QuickSight can show you the top customers that contributed to a spike in sale in the US for health products. This panel appears only if you chose fields to include in contribution analysis when you configured the anomaly.

    If you don't see this panel and you want to display it, you can enable it. To do this, return to the analysis, choose anomaly configuration from the insight's menu, and choose up to four fields to analyze for contributions. Keep in mind that if you make changes in the sheet controls that exclude the contributing drivers, the Contributions panel closes.