Stats 2

Card Set Information

Stats 2
2014-10-15 17:39:04
Psychology Stats
BSC Psychology Stats
Show Answers:

  1. What is sought in data analysis with regards to models?
    They must account for the variability in data
  2. What name is given to imperfect data?
    Unaccounted for
  3. How might one model be better than another?
    If it is more accurate (accounts for more of the variability)
  4. How are models improved?
    • By discovering relevant factors 
    • When taken into account, these help to explain more of the variation in data
  5. Why are models favoured by Scientists over anecdotal evidence?
    • Science attempts to create general laws
    • 'The purpose of formulating a model is not merely to account for the data at hand, but to use the data as a means of formulating a model that is 'true' more generally
  6. What is the difference between the particular and the general?
    Sample (particle) data are used to discover what is 'true' in the population (general)
  7. What is a signal?
    The model data
  8. What is noise?
    • Random fluctuations in the measurements of signal data
    • It is the task of that statistical analyst to distinguish the signal from the background noise
  9. What happens as the strength of background noise increases?
    • Our ability to detect the signal decreases
    • It is harder to discover the appropriate underlying model
    • The accuracy of the model predictions also decrease
  10. What is the general assumption when it comes to generalisation?
    If a model works well for existing data, it can be used to predict the outcomes of data not yet observed
  11. What is the principle of replicability?
    Identical conditions yield identical results
  12. What do models (signals) represent in terms of replicability?
    The regular, reliable components of data
  13. What does noise correspond to?
    Aspects of the data that are unstable and unpredictable
  14. What is assumed about noise with regards to replicability?
    • It is considered to be random 
    • It is the result of a multitude of small and random influences
  15. What does strict replicability demand?
    Precisely the same measurement must be obtained under every repetition of an observation under a given set of circumstances
  16. What does general replicability demand?
    • The repetition of an experiment should lead to the same general conclusion 
    • Numerical values need not be identical