Data recording and analysis

• What are descriptive statistics

  what data can tell us about behaviour
• What is a measure of central tendency

  an average. measures of central tendency are mean, mode and median. the range isn't a measure of central tendency
• What is the symbol for the mean

  mean =

  
• What is the equation for the mean

  mean = sum of each value in data set/number of participants in data set

  
• What is the mean + how to calculate

  the average, best MoCT but can be skewed by extreme values (outliers) - add up all the Nos in a data set and divide by the No of pieces of data
• What is the median + how to calculate

  the middle value when the raw data is placed in order (smallest to biggest), not affected by extreme values as they are marginalised but can be distorted by a small sample - put numbers in ascending order, find middle value (if 2 middle values add together + half)
• What is the mode + how to calculate

  the value or event that occurs most frequently, worst and most basic measure of central tendency - most frequent number in the data set
• What is the strength of the mean

  all of the data is used to calculate the answer - so its more representative of the data
• What is a weakness of the mean

  extreme scores (outliers/anomalies) can distort the value - so it's not an appropriate measure of central tendency if our data set is skewed
• What is a strength of the median

  extreme scores don't distort the value - so it's a robust measure of central tendency if our data is skewed by extreme values
• What is a weakness of the median

  it is difficult and time consuming to calculate with a large set of data.

  it's a less representative measure of central tendency because it doesn't depend on all the items in the data
• What is a strength of the mode

  its the only measure of central tendency we can use when data isn't numerical - so it allows for analysis of the most commonly occurring category
• What is a weakness of the mode

  it may not accurately reflect the data set - if there is no most frequent value it's effectively useless
• What to do if asked to outline a finding

  • state a simple finding (mean, median, mode - measures of central tendency, range, %, outliers) from the table/graph - don't just state highest and lowest, make it interesting
  • context e.g one finding from the table is that most participants (18) gave a shock level of 450 Volts
• What to do if asked to outline a conclusion

  • state a finding using raw data
  • make a suggestion/explain what this data means in the context of the study (this suggests...)
  • make an inference as to why (this could be because...) e.g one conclusion from table is 18 participants gave shock level of 450V, suggests most people will obey request even when it's unethical/causes harm, could be because participants hadn't encountered situation before + thought there'd be consequences for not following instruction