psych organising and interpreting data 1E

• Primary data


  Sourced firsthand through experimentation, observational studies, or self report
• Advantages of primary data

  • Specific and detailed
  • Can inform future research
  • Current
• Disadvantages of primary data

  • More expensive
  • Greater restrictions on sample size
• Secondary data


  Sourced through someone else's research or data sources
• Advantages of secondary data

  • Cheap
  • Easy to obtain
  • Large amounts of data
  • Collected over long periods of time
• Disadvantages of secondary data

  • Outdated
  • Not specific to research
• Qualitative data


  Data that is expressed non-numerically
• Quantitative data


  data that is expressed numerically
• Subjective data


  data that is informed by personal opinion, perception, or interpretation
• Advantages of subjective data

  • Detailed
  • Captures individual experience
• Disadvantages of subjective data

  • Open to interpretation and bias
• Objective data


  data that is observed and measured independently of personal opinion
• Advantages of objective data

  • Easily summarised
• Disadvantages of objective data

  • Can lack detail
• Descriptive statistics


  Mathematical calculations that describe, organise, and summarise the data
• Measures of central tendency

  • Mean
  • Median
  • Mode
• Mean


  describes the numerical average of a data set, expressed as a single value
• Median


  middle value in a data set ordered from lowest to highest
• Mode


  most frequently occurring value in a data set
• Outliers


  value that differs significantly from other values in a data set
• Percentages


  useful for descriptive statistics which is easier for researchers to easily notice patterns and trends.
• Measures of variability


  • Range
  • Standard deviation
• Range


  value obtained by subtracting the lowest value in a data set from the highest value
• Standard deviation


  expressed as a value that describes the spread of data around the mean
• Charts and graphs


  Used instead of tables when it is more important to show the trends, patterns, relationships and overall pictures of the data
• Bar graphs


  Used to display data that has discrete categories
• Line graphs


  Used when data is numerical and continuous
• Contrast primary and secondary data

  Primary data is first-hand research collected through experimentation, observation, or survey, whereas secondary data is sourced from others' prior research, obtained through publicly available databases or other researchers' data.

  
• Quantitative and qualitative data

  Quantitative data is numerical, like test scores or weight measurements, while qualitative data is non-numerical, like verbal descriptions. Both types are collected through methods like open-ended questionnaires and interviews, and can be converted into quantitative data through systematic methods.
• Objective and subjective data

  Objective data is factual, measured independently of personal opinion, whereas subjective data is informed by personal opinion or interpretation. Both are valuable in research but require verifiable data for accuracy.
• Measures of central tendency


  statistical measures that provide a summary of a data set by describing the data's distribution centre with a single value.
• Tables


  presentation of data arranged into columns and rows

  
• Bar charts


  graph displaying the relationship between at least two variables using rectangular bars with heights or lengths proportional to the values they represent

  
• Line graphs


  graph displaying the relationship between at least two variables using a straight line to connect data points

  
• What is the purpose of percentages and percentage change

  Summarise raw data into a meaningful value

  Allow for comparisons to be made between data points or sets
• What is the purpose of the mean?

  Describe the average of a data set

  Summarise the typical participant response or data when the data is evenly (normally) distributed
• What is the purpose of the median?

  Describe the middle value in a data set

  Summarise data, especially when the data is not evenly distributed or there are outliers
• What is the purpose of the mode?

  Describe the most frequently occurring data value

  Summarise data, especially when the mean and median cannot be calculated
• What is the purpose of the range?

  To summarise the overall dispersion of scores by describing the difference between the lowest and highest values in a data set
• What is the purpose of the standard deviation?


  Summarise the dispersion of data by describing the spread of data around the mean