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Accuracy to reference source

Characteristic Name: Accuracy to reference source
Dimension: Accuracy
Description: Data should agree with an identified source
Granularity: Element
Implementation Type: Process-based approach
Characteristic Type: Usage

Verification Metric:

The number of tasks failed or under performed due to lack of accuracy to reference sources
The number of complaints received due to lack of accuracy to reference sources

GuidelinesExamplesDefinitons

The implementation guidelines are guidelines to follow in regard to the characteristic. The scenarios are examples of the implementation

Guidelines: Scenario:
Establish the source for a data attribute and maintain facilities to access the correct source. (1) Actual Cost of raw material is taken from Supplier invoices and not from quotation.
(2) Interest rates are taken from daily central bank statistics which is available in the finance system online.
Establish the data capturing points in the business process without leading to any ambiguity and enforce process level validation mechanisms to ensure the process is being followed. (1) Personal drug utilisation data is captured at POS units at pharmacies and ALL pharmacies in the country are connected to a central system (All pharmacy data is considered). (2) In a barcode scanning system in a production system, finished products cannot be scanned into quality checked products (Finished, Quality checked are the two data capturing points here)
Implement effective techniques and efficient technological solutions (devices) in collecting data which minimise data errors and omissions in data capturing. (1) Barcode scanning is used to enter sales of products. (2) Invoices are scanned into the system and price is automatically recognised. (3) Standard forms are used to collect patient data.
If data is collected and transferred batch wise, establish the frequencies of data transfers/uploads considering the nature of the data and business needs. (1) All drug utilisation data collected in the pharmacies are transferred to the central system at the end of every month.
(2) Production efficiency data is transferred to monitoring systems every 30 minutes
Implement an effective and efficient data transferring technology which do not cause distortions or omissions to data (1) Data migration tools
Define and implement appropriate input validation rules to notify the data collector/operator about the erroneous values being entered, avoid erroneous values being entered into database or erroneous values are flagged for clear identification (1) Telephone number does not accept non numeric characters
Implement flexible data capturing interfaces to accommodate important but out of the way data. (1) A field exists to record special comments in a goods receipts note (GRN)
Implement and enforce standardised data capturing procedures/ best practices through the system in collecting data. (1) Standard wait times are used in taking blood samples of a patient.
(e.g.: one hour after meal)
Establish mitigation mechanisms to handle measurement errors and ensure that acceptable error tolerance levels are established (1) calibrate the equipments on a routine basis
Identify barriers for data collection or barriers for data providers and take appropriate actions to remove them (1) Maintain a log file of response failures of a web based survey and then eliminate the root causes.
Identify the practices which encourage data providers (1) Reward survey participants
Conduct regular training programs for data capturing/entering staff and educate them on possible data capturing problems and how to overcome data entry errors depending on the context (1) Do not restart the Scanner when it is hung up while scanning
(2) Repeat a telephone number in a different pattern to validate it from the source e.g. : 045 220 371 9 , in validating repeat it as 04 52 20 37 19

Validation Metric:

How mature is the process for ensuring accuracy for reference sources

These are examples of how the characteristic might occur in a database.

Example: Source:
In this scenario, the parent, a US Citizen, applying to a European school completes the Date of Birth (D.O.B) on the application form in the US date format, MM/DD/YYYY rather than the European DD/MM/YYYY format, causing the representation of days and months to be reversed. N. Askham, et al., “The Six Primary Dimensions for Data Quality Assessment: Defining Data Quality Dimensions”, DAMA UK Working Group, 2013.
, let us consider two

databases, say A and B, that contain the same data. If at time t a user updates data in database A and another user reads the same data from database B at time t' (t < t' ), the latter will read incorrect data. If t and f are included within the time interval between two subsequent data realignments

 C. Cappiello, C. Francalanci, and B. Pernici, “Time-Related Factors of Data Quality in Multichannel Information System” in Journal of Management Information Systems, Vol. 20, No. 3, M.E. Sharpe, Inc., 2004, pp.71-91.
Consider an air traffic control center which receives data from several controller stations. To regulate air traffic, the traffic control center has to cope with uncertain data.Thus, the decision process must balance the delaying receiving more accurate data of airplane positions and the critical period of time in which an“effective” decision must be made to regulate traffic; B. Pernici, “Advanced Information Systems Engineering” in proc. The 22nd International Conference, CAiSE, Hammamet, Tunisia, June 2010.

The Definitions are examples of the characteristic that appear in the sources provided.

Definition: Source:
A measure of the correctness of the content of the data (which requires an authoritative source of reference to be identified and accessible). D. McGilvray, “Executing Data Quality Projects: Ten Steps to Quality Data and Trusted Information”, Morgan Kaufmann Publishers, 2008.
The data agrees with an original, corroborative source record of data, such as a notarized birth certificate, document, or unaltered electronic data received from a party outside the control of the organization that is demonstrated to be a reliable source. ENGLISH, L. P. 2009. Information quality applied: Best practices for improving business information, processes and systems, Wiley Publishing.
1) Accuracy of data refers to how closely the data correctly captures what it was designed to capture. Verification of accuracy involves comparing the collected data to an external reference source that is known to be valid. Capturing data as close as possible to the point of activity contributes to accuracy. The need for accuracy must be balanced with the importance of the decisions that will be made based on the data and the cost and effort associated with data collection. If data accuracy is compromised in any way then this information should be made known to the data users.

2) Reliability of data refers to the extent to which data is collected consistently over time and by different organisations either manually or electronically.

HIQA 2011. International Review of Data Quality Health Information and Quality Authority (HIQA), Ireland. http://www.hiqa.ie/press-release/2011-04-28-international-review-data-quality.
Data accuracy refers to the degree with which data values agree with an identified source of correct information. There are different sources of correct information: database of record, a similar, corroborative set of data values from another table, dynamically computed values, the result of a manual workflow, or irate customers. LOSHIN, D. 2001. Enterprise knowledge management: The data quality approach, Morgan Kaufmann Pub.
Data accuracy refers to the degree with which data correctly represents the “real-life” objects they are intended to model. In many cases, accuracy is measured by how the values agree with an identified source of correct information (such as reference data). There are different sources of correct information: a database of record, a similar corroborative set of data values from another table, dynamically computed values, or perhaps the result of a manual process. LOSHIN, D. 2006. Monitoring Data quality Performance using Data Quality Metrics. Informatica Corporation.
Accuracy of datum refers the nearness of the value v to some value v’ in the attribute domain, which is considered as the (or maybe only a) correct one for the entity e and the attribute a. In some cases, v’ is referred to as the standard. If the datum’s value v coincides value v’, the datum is said to be correct. REDMAN, T. C. 1997. Data quality for the information age, Artech House, Inc.
Degree of correctness of a value when comparing with a reference one STVILIA, B., GASSER, L., TWIDALE, M. B. & SMITH, L. C. 2007. A framework for information quality assessment. Journal of the American Society for Information Science and Technology, 58, 1720-1733.
The extent to which data are correct reliable and certified free of error. WANG, R. Y. & STRONG, D. M. 1996. Beyond accuracy: What data quality means to data consumers. Journal of management information systems, 5-33.

 

Value consistency

Characteristic Name: Value consistency
Dimension: Consistency
Description: Data values are consistent and do not provide conflicting or heterogeneous instances
Granularity: Element
Implementation Type: Rule-based approach
Characteristic Type: Declarative

Verification Metric:

The number of inconsistent data values reported in an attribute per thousand records

GuidelinesExamplesDefinitons

The implementation guidelines are guidelines to follow in regard to the characteristic. The scenarios are examples of the implementation

Guidelines: Scenario:
For critical data elements provide standard classifications (values lists) for data entry interfaces and restrict arbitrary values across the system (1) Country, city are taken from a standard list.
(2) Generally accepted industry classifications are used to analyse customers industry wise (Education, Banking & Finance, Medical, Manufacturing…….
When data elements are combined for specific identification/management/accounting purposes, standardise such combinations and use them across the system. (1) Customer and sales order are combined for identification purposes
(2) Costs of wastage are associated with individual orders they are incurred and managed.
Define data attributes in such a way that data values are atomic and hence consistency can be maintained for any form of aggregation or consolidation Name is divided into first name Middle name and Last Name
Maintain consistency in using unit of measures across different tables and different data bases Sales price is in $ in Sales table and Accounts receivable ledger

Validation Metric:

How mature is the creation and implementation of the DQ rules to maintain value consistency

These are examples of how the characteristic might occur in a database.

Example: Source:
School admin: a student’s date of birth has the same value and format in the school register as that stored within the Student database. N. Askham, et al., “The Six Primary Dimensions for Data Quality Assessment: Defining Data Quality Dimensions”, DAMA UK Working Group, 2013.
For example, data are inconsistent when it is documented that a male patient has had a hysterectomy. B. Cassidy, et al., “Practice Brief: Data Quality Management Model” in Journal of AHIMA, 1998, 69(6).
the name of the city and the postal code should be consistent. This can be enabled by entering just the postal code and filling in the name of the city systematically through the use of referential integrity with a postal code table Y. Lee, et al., “Journey to Data Quality”, Massachusetts Institute of Technology, 2006.
the data values ST Louis and Saint Louis may both refer to the same city. However, the recordings are inconsistent, and thus at least one of them is inaccurate. J. E. Olson, “Data Quality: The Accuracy Dimension”, Morgan Kaufmann Publishers, 9 January 2003.

The Definitions are examples of the characteristic that appear in the sources provided.

Definition: Source:
Domain Level: The data values persist from a particular data element of the data source to another data element in a second data source. Consistency can also reflect the regular use of standardized values, articularly in descriptive elements. Entity Level: The entity’s domains and domain values either persist intact or can be logically linked from one data source to another data source. Consistency can also reflect the regular use of standardized values particularly in descriptive domains. B. BYRNE, J. K., D. MCCARTY, G. SAUTER, H. SMITH, P WORCESTER 2008. The information perspective of SOA design Part 6:The value of applying the data quality analysis pattern in SOA. IBM corporation.
Determines the extent to which distinct data instances provide nonconflicting information about the same underlying data object. For example, the salary range for level 4 employees must be between $40,000 and $65,000. G. GATLING, C. B., R. CHAMPLIN, H. STEFANI, G. WEIGEL 2007. Enterprise Information Management with SAP, Boston, Galileo Press Inc.
Data is consistent if it doesn’t convey heterogeneity, neither in contents nor in form – anti examples: Order.Payment. Type = ‘Check’; Order. Payment. CreditCard_Nr = 4252… (inconsistency in contents); Order.requested_by: ‘European Central Bank’;Order.delivered_to: ‘ECB’ (inconsistency in form,because in the first case the customer is identified by the full name, while in the second case the customer’s acronym is used). KIMBALL, R. & CASERTA, J. 2004. The data warehouse ETL toolkit: practical techniques for extracting. Cleaning, Conforming, and Delivering, Digitized Format, originally published.
Consistency can be curiously simple or dangerously complex. In its most basic form, consistency refers to data values in one data set being consistent with values in another data set. Two data values drawn from separate data sets may be consistent with each other, yet both can be incorrect. LOSHIN, D. 2001. Enterprise knowledge management: The data quality approach, Morgan Kaufmann Pub.
In its most basic form, consistency refers to data values in one data set being consistent with values in another data set. A strict definition of consistency specifies that two data values drawn from separate data sets must not conflict with each other, although consistency does not necessarily imply correctness. LOSHIN, D. 2006. Monitoring Data quality Performance using Data Quality Metrics. Informatica Corporation.
Consistency, in popular usage, means that two or more things do not conflict with one another. This usage extends reasonably well to data values, although a bit of added discipline is desired. REDMAN, T. C. 1997. Data quality for the information age, Artech House, Inc.