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How reliable are the data; what problems remain?

1. What can you say about the accuracy of the observations?

   Data_Quality_Information:
     Attribute_Accuracy:
       Attribute_Accuracy_Report:  Information and advice
   

   The report should include a summary of the processes by which the attribute data have been reviewed or tested, including results.
   Optionally, if you have statistics on the accuracy of the attributes, include for each statistic the following elements:

       Quantitative_Attribute_Accuracy_Assessment:
         Attribute_Accuracy_Value:  A statistic
         Attribute_Accuracy_Explanation: What the statistic means
   

2. How accurately are the geographic locations known?

   Data_Quality_Information:
     Positional_Accuracy:
       Horizontal_Positional_Accuracy:
         Horizontal_Positional_Accuracy_Report:  Information and advice
   

   This report should include a summary of the processes by which the geographic positions have been reviewed or tested, including results.
   Optionally, if you have statistics on the accuracy of the locations, include for each statistic the following elements:

         Quantitative_Horizontal_Positional_Accuracy_Assessment:
           Horizontal_Positional_Accuracy_Value:  A statistic
           Horizontal_Positional_Accuracy_Explanation: What the statistic means
   

3. If data vary in depth or height, how accurately is vertical position known?
   This is like Horizontal_Positional_Accuracy; just swap "Vertical" for "Horizontal" in all of the element names:

   Data_Quality_Information:
     Positional_Accuracy:
       Vertical_Positional_Accuracy:
         Vertical_Positional_Accuracy_Report:  Information and advice
   

   This report should include a summary of the processes by which the elevations or depths have been reviewed or tested, including results.
   Optionally, if you have statistics on the accuracy of the elevations or depths, include for each statistic the following elements:

         Quantitative_Vertical_Positional_Accuracy_Assessment:
           Vertical_Positional_Accuracy_Value:  A statistic
           Vertical_Positional_Accuracy_Explanation: What the statistic means
   

4. Where are the gaps in the data? What is missing there?

   Data_Quality_Information:
     Completeness_Report:  Information and advice
   

5. Do the observations mean the same thing throughout the data set?
   • What contextual factors should be considered by someone who wants to understand the data?
   • Did the instrumentation or calibration change while observations were being made?
   • Does it matter who made the observations? If so, did more than one person make observations?

   Data_Quality_Information:
     Logical_Consistency_Report:  Information and advice
   

   If you have contact information for people who did some of the data collection or data processing but aren't authors, you can include that contact information in the Process_Contact section of the Lineage (see Are the data original observations of the authors? and How were the source data modified?).