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A '''data map''' is a template designed by [https://www.worldbank.org/en/research/dime DIME] for organizing the 3 main aspects of '''data work''': [[Data Analysis|data analysis]], [[Data Cleaning|data cleaning]], and [[Data Management|data management]]. It consists of three components: a [[Data Linkage Table|data linkage table]], a [[Master Dataset|master dataset]], and [[Data Flow Charts|data flow charts]]. [https://www.worldbank.org/en/research/dime/data-and-analytics DIME Analytics recommends using these components to organize the various your data work using these tools will make your data work more efficient, and will increase the quality of your data and, therefore, of your research.
A '''data map''' is a template designed by [https://www.worldbank.org/en/research/dime/data-and-analytics DIME Analytics] for organizing the 3 main aspects of '''data work''': [[Data Analysis|data analysis]], [[Data Cleaning|data cleaning]], and [[Data Management|data management]]. The '''data map template''' consists of three components: a [[Data Linkage Table|data linkage table]], a [[Master Dataset|master dataset]], and [[Data Flow Charts|data flow charts]]. [https://www.worldbank.org/en/research/dime/data-and-analytics DIME Analytics] recommends using '''data maps''' to organize the various components of your '''data work''' in order to increase the quality of data, as well as of research.


== Read First ==
* The best time to start creating a '''data map''' is before starting with [[Primary Data Collection|data collection]].
* A '''data map template''' has three components: a [[Data Linkage Table|data linkage table]], one or more [[Master Dataset|master datasets]], and one or more [[Data Flow Charts|data flow charts]].
* The [[Impact Evaluation Team|research team]] should keep updating the '''data map''' as the project moves forward.
* The '''data map template''' is meant to act as a starting point for [[Data Management|data management]] within a '''research team'''.
* It is important to understand the underlying '''best practices''' for each component of a '''data map''' before discussing which components do not apply in a given situation.


Read first
== Overview ==
- Your Data Plan has three components: a Data Linkage Table, Master Dataset(s), and Data Flow Chart(s)
Most of the details required for preparing a '''data map''' are not complex. For example, it is easy for the [[Impact Evaluation Team#Field Coordinators (FCs)|field coordinator (FC)]] to remember what the '''respondent ID''' is when [[Primary Data Collection|data collection]] is still ongoing. However, it is harder to ensure that everyone in the [[Impact Evaluation Team|research team]] has the same level of understanding. Further, as time passes, the '''field coordinator (FC)''' themselves can forget what exactly a particular variable measures, or why it was included in the dataset. '''Research teams''' often do not spend enough time planning and organizing '''data work''' because small details like the purpose of a variable might seem obvious. However, this lack of proper planning is a common source of error. Fortunately, the solution is to create a '''data map''', which is quick and easy to implement.
- While the best time to start your data plan is before you start acquiring data, it is never too late. You should keep updating your data plan as your project evolves.
- If you are in the middle or towards the end of your project and you spend more time linking your datasets than doing other data work, you should step back and create a data plan.
- As with all templates, you might need to add items to our Data Plan Template or you may find that some items do not apply. The template is meant to be the starting point for a conversation about your team’s data needs and organization. Make sure that you understand the underlying best practice for each item in the template before you decide that it does not apply.


[https://www.worldbank.org/en/research/dime/data-and-analytics DIME Analytics] has prepared a '''data map template''', which has the following three components:
 
* A [[Data Linkage Table|data linkage table]]: The '''data linkage table''' lists all the datasets in a particular project, and explains how they are linked to each other. For example, a '''data linkage table''' can describe how a dataset containing information about students can be merged with a dataset containing information about various schools. It also specifies which [[ID Variable Properties|ID variable]] can be used to perform the merging. Finally, the data linkage table should also include '''meta-information''', that is, information about the datasets, where the original version of these data sets are backed-up, and so on.


Overview
* One or more [[Master Dataset|master datasets]]: '''Master datasets''' allow the [[Impact Evaluation Team|research team]] to keep track of [[Unit of Observation|units for each level of observation]]. For example, '''master datasets''' are useful for keeping track of each household if the '''unit of observation''' is individual households, each company if the '''unit of observation''' is individual companies, and so on. Most importantly, the master dataset should specify the [[ID_Variable_Properties#Property_1:_Uniquely_Identifying|uniquely]] and [[ID_Variable_Properties#Property_2:_Fully_Identifying|fully identifying]] '''ID variable''' for each unit of observation. Include variables related to the research design in the master dataset, such as [[Randomized_Control_Trials#Randomized_Assignment|treatment assignment variables]] in the form of '''dummy variables'''. The master dataset is therefore the authoritative source of all information in a particular project.


Most of the details required for a data plan are not complex by themselves. It is, for example, easy for the field coordinator to remember what the respondent ID is, during the time of that data collection activity. However, maintaining a shared understanding across time and team members - so that details are used consistently throughout the project - is not straightforward. Because details seem obvious in the short run, project teams often do not spend enough time planning and organizing data work. This tendency makes poor data planning a common source of error. Fortunately the solution - a data plan - is quick and easy to implement.  
* One or more [[Data Flow Charts|data flow charts]]: A '''data flow chart''' specifies which datasets are needed to create the [[Data Analysis|analysis dataset]], and how they may be combined by either '''appending''' or '''merging''' datasets. This means that there should be one data flow chart per '''analysis dataset'''. Make sure that every original dataset that is mentioned in a data flow chart should be listed in the '''data linkage table'''. For example, in a particular data flow chart, information about which variables to use as the basis for merging datasets should correspond to the information in the data linkage table.  


The DIME Analytics data plan template has three components: a Data Linkage Table, one or several Master Datasets and one or several Data Flow Charts. The data linkage table lists all the datasets in your project and how they link to each other. For example, it would describe how a student dataset can be merged to a school dataset, and which ID variable can be used to do so. The data linkage table also includes meta-information, such as where the original version of these data sets are backed-up, etc. There should only be one data linkage table per project. See below for templates, examples, best practices and other details.
'''Note''' - Please keep the following points in mind regarding '''data maps''':  
* '''A good data map can save a lot of time'''. Sometimes research teams realize that they are spending more time on linking datasets instead of actually [[Data Analysis|analyzing data]]. In such cases, creating a data map can save a lot of time.  


The master dataset(s) are how you keep track of units for each level of observation. For example, keeping track of each household if your unit of observation is households, each company if your unit of observation is companies, etc. Most importantly, the master dataset specifies the uniquely and fully identifying ID variable for each unit. The master dataset should also include variables related to the research design, such as sample and treatment assignment variables. The master dataset should be the authoritative source of all information included. Many projects have multiple units of observation, requiring one master data set for each unit of observation that is central to the research. See below for details on what units are central and other details and best practices for master datasets.
* '''It is never too lat to create a data map'''. Even if the research team is in the middle of a project, or nearing the end of a project, it is still a good idea to pause and create a data map if it is becoming difficult to keep track of various aspects of the data.


The final component in the DIME Analytics data plan template is the data flow charts. There should be one flow chart per analysis data set in the project. Each data flow chart shows what datasets are needed to create the analysis dataset and how they may be combined by appending or merging them. All original datasets in a data flow chart should be listed in the data linkage table; the information in the data flow chart, for example, which variables to merge datasets on, should correspond to the information in the data linkage table. See below for more examples, best practices and other details related to data flow chart.
* '''Modify the data map based on the context.''' As with all templates, the research team might need to add items to the data map template, or may find that some components do not apply in a particular context.
 
* '''There can be multiple master datasets, but only one data linkage table.''' Many projects have multiple units of observation, in which case there should be one master datase for each unit of observation that is considered central to the project. However, there should only be one data linkage table per project.
 
== Data Linkage Table ==
The point of the data linkage table is to ensure that you can accurately and reproducibly link all datasets associated with your project. Data linkage errors are common. For example, you may have two datasets with the same units (companies, health workers, court cases etc.) but no way to easily merge or append them. You might have to do a fuzzy match on string variables or sets of descriptive characteristics, which is always a time-consuming and error-prone process that cannot scale with additional data.
 
== Master Dataset ==
Most research projects, especially impact evaluations, collect and/or use multiple datasets for a given [[Unit of Observation|unit of observation]]. A master dataset is a comprehensive listing of the fixed characteristics of the observations that might occur in any other project dataset. Therefore, it contains one entry for each possible observation of a given unit of observation that a research team could ever work with in the project context via [[Sampling & Power Calculations | sampling]], surveying, or otherwise. While master datasets take some time and effort to set up, they dramatically mitigate sources of error and simplify working with datasets from multiple sources (i.e. baseline data, endline data, [[Administrative and Monitoring Data | administrative and monitoring data]], etc.).
 
== Data Flow Charts ==
Data flow charts can be very simple, for example, when your analysis dataset is created by appending the baseline data with the endline data. But even in a simple case like that, you often realize that there is some administrative data, treatment statuses, monitoring data, etc. that is also needed when writing the data flow chart. Mapping all those needs and documenting them well in both the data flow charts and the data linkage map is the best way to guarantee that you find yourself in a situation where you cannot construct the analysis data as you do not have all the datasets you need, or the datasets you have does not have the information needed to create the analysis dataset.
 
== Related Pages ==
[[Special:WhatLinksHere/Data_Map|Click here to see pages that link to this topic]].

Revision as of 14:07, 9 September 2020

A data map is a template designed by DIME Analytics for organizing the 3 main aspects of data work: data analysis, data cleaning, and data management. The data map template consists of three components: a data linkage table, a master dataset, and data flow charts. DIME Analytics recommends using data maps to organize the various components of your data work in order to increase the quality of data, as well as of research.

Read First

  • The best time to start creating a data map is before starting with data collection.
  • A data map template has three components: a data linkage table, one or more master datasets, and one or more data flow charts.
  • The research team should keep updating the data map as the project moves forward.
  • The data map template is meant to act as a starting point for data management within a research team.
  • It is important to understand the underlying best practices for each component of a data map before discussing which components do not apply in a given situation.

Overview

Most of the details required for preparing a data map are not complex. For example, it is easy for the field coordinator (FC) to remember what the respondent ID is when data collection is still ongoing. However, it is harder to ensure that everyone in the research team has the same level of understanding. Further, as time passes, the field coordinator (FC) themselves can forget what exactly a particular variable measures, or why it was included in the dataset. Research teams often do not spend enough time planning and organizing data work because small details like the purpose of a variable might seem obvious. However, this lack of proper planning is a common source of error. Fortunately, the solution is to create a data map, which is quick and easy to implement.

DIME Analytics has prepared a data map template, which has the following three components:

  • A data linkage table: The data linkage table lists all the datasets in a particular project, and explains how they are linked to each other. For example, a data linkage table can describe how a dataset containing information about students can be merged with a dataset containing information about various schools. It also specifies which ID variable can be used to perform the merging. Finally, the data linkage table should also include meta-information, that is, information about the datasets, where the original version of these data sets are backed-up, and so on.
  • One or more master datasets: Master datasets allow the research team to keep track of units for each level of observation. For example, master datasets are useful for keeping track of each household if the unit of observation is individual households, each company if the unit of observation is individual companies, and so on. Most importantly, the master dataset should specify the uniquely and fully identifying ID variable for each unit of observation. Include variables related to the research design in the master dataset, such as treatment assignment variables in the form of dummy variables. The master dataset is therefore the authoritative source of all information in a particular project.
  • One or more data flow charts: A data flow chart specifies which datasets are needed to create the analysis dataset, and how they may be combined by either appending or merging datasets. This means that there should be one data flow chart per analysis dataset. Make sure that every original dataset that is mentioned in a data flow chart should be listed in the data linkage table. For example, in a particular data flow chart, information about which variables to use as the basis for merging datasets should correspond to the information in the data linkage table.

Note - Please keep the following points in mind regarding data maps:

  • A good data map can save a lot of time. Sometimes research teams realize that they are spending more time on linking datasets instead of actually analyzing data. In such cases, creating a data map can save a lot of time.
  • It is never too lat to create a data map. Even if the research team is in the middle of a project, or nearing the end of a project, it is still a good idea to pause and create a data map if it is becoming difficult to keep track of various aspects of the data.
  • Modify the data map based on the context. As with all templates, the research team might need to add items to the data map template, or may find that some components do not apply in a particular context.
  • There can be multiple master datasets, but only one data linkage table. Many projects have multiple units of observation, in which case there should be one master datase for each unit of observation that is considered central to the project. However, there should only be one data linkage table per project.

Data Linkage Table

The point of the data linkage table is to ensure that you can accurately and reproducibly link all datasets associated with your project. Data linkage errors are common. For example, you may have two datasets with the same units (companies, health workers, court cases etc.) but no way to easily merge or append them. You might have to do a fuzzy match on string variables or sets of descriptive characteristics, which is always a time-consuming and error-prone process that cannot scale with additional data.

Master Dataset

Most research projects, especially impact evaluations, collect and/or use multiple datasets for a given unit of observation. A master dataset is a comprehensive listing of the fixed characteristics of the observations that might occur in any other project dataset. Therefore, it contains one entry for each possible observation of a given unit of observation that a research team could ever work with in the project context via sampling, surveying, or otherwise. While master datasets take some time and effort to set up, they dramatically mitigate sources of error and simplify working with datasets from multiple sources (i.e. baseline data, endline data, administrative and monitoring data, etc.).

Data Flow Charts

Data flow charts can be very simple, for example, when your analysis dataset is created by appending the baseline data with the endline data. But even in a simple case like that, you often realize that there is some administrative data, treatment statuses, monitoring data, etc. that is also needed when writing the data flow chart. Mapping all those needs and documenting them well in both the data flow charts and the data linkage map is the best way to guarantee that you find yourself in a situation where you cannot construct the analysis data as you do not have all the datasets you need, or the datasets you have does not have the information needed to create the analysis dataset.

Related Pages

Click here to see pages that link to this topic.