Inferential Statistics

Card Set Information

Inferential Statistics
2014-04-17 21:15:18
Psychology Methodology

AQA PSYB4 Research Methods
Show Answers:

  1. When are inferential statistics used?
    When psychologists wish to make inferences about collected data in order to estimate the likelihood that the data collected occurred due to chance or to draw conclusions about a larger population from which the sample was collected
  2. What are parametric tests?
    • More powerful and robust methods of analysis 
    • More accurate estimates of probabilities are collected, making type 1 and 2 errors less likely to occur
  3. In order for data to be parametrically tested, what criteria must be met?
    • The data must be precise, interval level of measurement 
    • Scores must be drawn from a normal distribution of the population with few scores at both ends and more in the middle 
    • The variability of the two sets of the scores must be similar
  4. How could a researcher test the distribution of data collected?
    • The mean, median and mode are compared
    • If the data is of a normal distribution, these figures should be similar
  5. What is the homogeneity of variance?
    The standard deviation2  

  6. How might one measure the variability of the data sets collected?
    • The range
    • The standard deviation
    • The variance 
    • Dot plot or box plots
  7. What requirements must be met in order for non parametric tests to be employed?
    • The data must be nominal or ordinal 
    • Results must be of a skewed distribution
    • There must be a wide variance in scores between two sets
  8. What questions should you ask yourself before choosing a statistical test?
    • Am I looking for a difference between scores or a correlation?
    • What type of design have I used?
    • What level of measurement have I used?