Primary and Secondary Data

Primary Data

• Gathered first hand by a researcher.
• Psychological studies usually gather primary data via; observation, questionnaires, case studies and experiments, which can be qualilative and quantitative.
• Examples of Experiments which used PRIMARY DATA.
• Milgram (obedience on induviduals in a lab)
• Bandura (observation of children copying role models)

• Evaluation of Primary Data
• Strengths
• Primary data, in general is relaible because the researcher can replicate procedures to check the results, as they know, the procedures and how the data was collected and analysed.
• Primary data is taken directly from the population in question, it is one of the best types of data to collect for research methods like the survey.
• The data is being used for the purpose intedned so are liklely to be relevent to the study compared to sceondary data.
• Researchers are in contact with their participants, and can be sensitive to any issues that arise, such as distress to participants.
• Its more likely to be up to date, so is more valid.

• Evaluation of Primary Data 
• Weaknesses
• Data has to be gathered froms scratch, which involves finding a large enough population to make the sample credible, representative and generalisable, this makes it more costly and time consuming. If the sample is too small, it is much harder to draw conclusions.
• Researchers may be subjective in what kinda of data they look for, and alter it to their hypothesis (researcher bias)
• More liklely to expolit participants than secondary data. 

• Secondary Data
• Has already been gathered by somebody else, and is used by somebody else for further research.
• It is the second hand analyisis of pre-existing data.
• E.g. government statistics from a census, can give information on many aspects, e.g. females living alone.
• A meta analysisis where researchers pool data on a particular topic, using secondary data as the data which is studied is not gathered first hand.
• It is sometimes gathered before primary research. in order to find out what is already known about a subject before carrying out a new investigation.
• Examples: Freud; Little Hans (self-report), Bacarac (meta-analysis), Rosenthal and Jacobsen (IQ) and Raine (Brain Scan)

Evaluation of Secondary Data

• Strengths
• Saves time and expenses that could otherwise be spent collecting data.
• It can provide a large data base than an induvidual researcher could hope to collect.
• In some cases, e.g historical documents, secondary data is often the only reource and this the only wat to examine large scale trends of the past.
• Less likely for ethical issues to occur, as the data isn't taken directly from participants, and the information is already in the public domain.

Evaluation of Secondary Data

• Weaknesses
• The researcher cannot personally check the data so its reliability may be questioned.
• Researcher may not know how the data was orginally collected, and has no control over that. Therfore they don't know anything about its accuracy.
• The data may be out of date, and therefore not suitable for the research, as there are issues with validity and relevance.
• Reliability and validity are unknown, so data may be flawed.
• There are issues with the interpretation of this data, as the data may have been collected under a different intention.