Probability

• What is data?

  Data is a collection of numerical figures and information used in research.
• What are the processes involved in data handling?

  • Developing questions
  • Collecting data
  • Classifying and organizing data
  • Summarising data
  • Interpreting and analysing data
  • Representing data
• Why is it important to state the aim of the research clearly?

  It guides the formulation of the tool to collect data.
• What types of questions can be used to collect data?

  Open-ended and closed questions.
• What is an open-ended question?


  An open-ended question allows respondents to answer in their own words.
• What is a disadvantage of open-ended questions?


  Respondents might leave it out if it takes too long to answer.
• What is a closed question?

  A closed question provides options for the respondent to choose from.
• What is a disadvantage of closed questions?

  They may not accommodate all respondents, leading to unanswered questions.
• How does the aim of the research influence data collection?

  It influences the choice of the sample and the method of collecting data.
• What is a sample in research?

  A sample is a portion chosen to represent the population.
• What is sample bias?

  Sample bias occurs when the sample is not representative of the population.
• How can random sampling minimize sample bias?

  It ensures that every member of the population has an equal chance of being selected.
• What are the three methods of collecting data?

  Observation, questionnaire, and interview.
• What is the advantage of using observation as a data collection method?

  You don’t interact with people to get the response.
• What is a questionnaire?

  A questionnaire is a list of questions used to collect data from respondents.
• What is the advantage of using a questionnaire?

  You get the information directly from the participants.
• What is an interview in data collection?

  An interview involves asking questions and recording the responses.
• What is the advantage of using an interview?

  The interviewer may ask further questions if the response is vague.
• What does organizing data involve?

  Arranging information into some kind of order.
• What does classifying data mean?

  Organizing it in groups or classes based on some common feature.
• How can data be organized?

  By using tally marks.
• What is the purpose of summarising data?

  To describe the whole data set using just a few numbers.
• What are measures of central tendency?

  Single values that attempt to show a central position of a set of data.
• What are the three types of measures of central tendency?

  Mean, mode, and median.
• What is the mean?

  The mean is the average calculated by adding all values and dividing by the number of values.
• What is the median?

  The median is the middle number in a data set when arranged in order.
• How do you determine the median in an even set of data?

  Add the two middle numbers and divide by 2.
• What is the mode?

  The mode is the data value that appears most often in a set of data.
• What is the range?

  The range is the difference between the largest and smallest values in a data set.
• What does a small range indicate about data values?

  A small range suggests that the values are grouped closer to the median.
• What are quartiles?

  Quartiles are divisions of data into four equal parts.
• How do you determine the interquartile range?

  It is the difference between the upper quartile and the lower quartile.
• What is the five number summary in data analysis?

  • Minimum value
  • Lower quartile (Q1)
  • Median (Q2)
  • Upper quartile (Q3)
  • Maximum value
• What is an outlier?

  An outlier is an extremely low or extremely high value in a data set.
• How do you calculate the range of the data set: 3, 7, 8, 5, 4, 10?

  The range is $10 - 3 =$$7$.
• What is the range of the data set: 2, 75, 79, 83, 86, 86, 89, 99?

  The range is $99 - 2 =$$97$.
• How do you find the median of the data set: 0, 0, 1, 1, 1, 2, 2, 2, 3, 3, 3, 3, 4, 4, 5, 5, 6, 6, 6, 7, 7?

  The median is $3$ (the middle value).
• How do you determine the quartiles of a data set?

  First find the median, then divide the lower and upper halves to find Q1 and Q3.
• How do you calculate the interquartile range?

  Subtract the lower quartile from the upper quartile.
• Why might the range be misleading in data interpretation?

  It only indicates the spread between the lowest and highest values, which can be misleading.