Data collection serves as the foundation for the entire study, ensuring that relevant and accurate information is gathered for analysis. The main sources and types of research data, and some common data collection methods are listed as follows.
Main Types and Sources of Research Data
Type | Description | Source |
Primary Data | Original and firsthand data collected directly by researchers for a specific research purpose |
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Secondary Data | Data that has already been collected, analyzed, and published by someone else |
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Qualitative Data |
A descriptive type of data and is often collected through methods such as interviews, focus groups, and observations |
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Quantitative Data | Data that is numerical and can be measured and analyzed statistically |
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Sensor and Instrument Data | Data that is collected using various sensors and instruments, often in scientific and engineering research |
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Administrative Data | Data that is collected by organizations or institutions as part of their routine operations |
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Big Data | This refers to large and complex datasets that require advanced methods for storage, processing, and analysis |
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Common Data Collection Methods
Experiments | This involves manipulating one or more variables to determine their effect on other variables. Experiments are often conducted in controlled environments and are common in scientific research. |
Case Studies | This method involves an in-depth analysis of a single case or a small number of cases. It is useful for exploring complex phenomena in detail. |
Observations | Researchers collect data by observing subjects in their natural environment. This method is often used in ethnographic studies and can be either participant or non-participant observation. |
Surveys and Questionnaires | These are used to gather data from a large number of respondents. They can be administered in person, over the phone, via mail, or online. Surveys can include open-ended questions, closed-ended questions, or a mix of both. |
Interviews | This method involves direct, one-on-one interaction between the researcher and the participant. Interviews can be structured, semi-structured, or unstructured, depending on the level of flexibility desired. |
Focus Groups | This involves guided discussions with a group of people to gather diverse perspectives on a particular topic. It is useful for exploring complex issues and generating ideas. |
Document and Content Analysis | This involves analyzing existing documents, texts, or media to extract relevant information. It is often used in historical research or media studies. |
Secondary Data Analysis | Researchers use existing data collected by other researchers or organizations. This can include datasets from government agencies, research institutions, or commercial entities. |
Handling Sensitive Data
Before sharing data publicly or storing it long-term, ensure data privacy by anonymizing personal information, encrypting sensitive data, and implementing strict access controls. This protects individuals' privacy and complies with legal and ethical standards.
Data Classification
City University of Hong Kong has released the least Information Classification and Handling Standard to the public, indicating all its information assets into appropriate levels to indicate the need, priority and degree of protection required. Please refer to Information Classification and Handling Standard , created by Computing Service Centre, City University of Hong Kong for details.
Data Encryption
Data encryption is a critical component ensuring that sensitive information remains secure and inaccessible to unauthorized users. Data encryption transforms readable data (plaintext) into an unreadable format (ciphertext) using algorithms and keys. The details of such technologies could be found on the webpage of Encryption for Information Protection , created by Computing Service Centre, City University of Hong Kong.
Apart from adopting the security technologies, below are some practices to protect individual identities without relying on technical security measures.
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For enquiries, please contact the Library's Research Data Management Services of the Research Support and Scholarly Communication Section at lbrdms@cityu.edu.hk