Stats

• What type of data includes categorical observations?

  Qualitative
• What type of data consists of numerical observations?

  Quantitative
• What are discrete data?

  Data that only take specific values
• What are continuous data?

  Data that can take any value within a range
• What is primary data?

  Data collected by the researcher
• What is secondary data?

  Data collected by other people
• What does the term 'population' refer to in sampling?


  Everything that could be included in the study
• What is a census?

  A survey of the whole population
• What is sampling?

  A part of people/items to be studied
• What are the types of sampling methods?

  • Systematic Sampling
  • Random Sampling
  • Stratified Sampling
  • Quota Sampling
• How do you find the interval for systematic sampling?

  Population size divided by sample size
• What is random sampling?

  Using a random number generator for selection
• What is stratified sampling?

  Dividing population into strata and sampling each
• What is quota sampling?

  Non-random selection with a target number
• What are the methods of data collection?

  • Questionnaires
  • Interviews
  • Observations
  • Experiments
• What are the advantages of questionnaires?

  Quick, cheap, and easy to distribute
• What is a disadvantage of interviews?

  Interviewer bias can occur
• What is a benefit of observations?

  Can observe natural behavior
• What is a disadvantage of experiments?

  Can lack ecological validity
• What does the person-capture response formula represent?

  It estimates response rates in surveys
• What is the formula for sample size in the person-capture response formula?

  $n =$$r / (1 - p)$
• What does 'p' represent in the formula?

  Proportion of unanswered questionnaires
• What are the steps in the number of response method?

  1. Find total number of questionnaires
  2. Find total who answered
  3. Find number of unanswered
  4. Estimate proportion of unanswered
  5. Estimate proportion of unavailable
  6. Work out total percentage
• What is the mode in measures of central tendency?

  Most common value
• What is the median in measures of central tendency?

  Middle value
• How do you calculate the mean?

  Sum of values divided by number of values
• What is the range in measures of dispersion?

  Largest value minus smallest value
• What is the interquartile range (IQR)?

  Upper quartile minus lower quartile
• How do you find the upper quartile (UQ)?

  $(n + 1) / 4\text{th value}$
• How do you find the lower quartile (LQ)?

  $(3(n + 1)) / 4\text{th value}$
• What is frequency density in histograms?

  Frequency divided by class width
• What is qualitative data?

  Non-numerical observations
• What is an example of qualitative data?

  Colour of cars
• What is categorical data?

  Data that can be put into categories
• What is ordinal data?

  Data that can be put into order
• What is nominal data?

  Data that cannot be ordered
• What is discrete data?

  Data that can only take certain values
• What is continuous data?

  Data that can take any value within a range
• What is bivariate data?

  Data collected from two variables at once
• What are the uses of bivariate data?

  • Correlation: association between variables
  • Regression: inference of influence between variables
  • Independent variable: the variable changed
  • Dependent variable: the variable that changes