Studies and Variables Solutions

Studies


• The researcher determines the type of study by defining:

  •    the purpose of the study
   
  •    the data that needs to be collected    

•    Observational Study    : through observation only, conclusions are drawn by a researcher, with no attempt to influence the responses of individuals

•    Sample Survey    : through researcher questionnaires or interviews, conclusions are drawn about the population using the sample

•    Experiment    : through researcher-designed treatment plans, conclusions are drawn by comparing the experimental and control groups


Variables


• Variables are    collected from individuals     and are either:

  •    Quantitative data    : numerical values that include counts and measures (height, arm span) upon which calculations can be performed.

  •    Categorical data    : characteristics or categories (eye color, birth month), and may also be referred to as “Qualitative.”

Example 3

Name the type of study conducted and if the variables are quantitative (Q) or categorical (C).

Example 4

Name the type of study and classify the variable(s).  

To assess the impact of a new fertilizer, a study was conducted on two apple orchards. Orchard A received the new fertilizer. Orchard B was treated with the standard fertilizer. The aim was to determine if a significant difference in fruit production existed between the apple trees in Orchard A and Orchard B.

Study: experiment
Variable: fruit production (Q)

Example 5

Name the population and type of study. Then classify the variable(s).  

The Madison High student council needs help selecting the theme for the upcoming school dance. At every lunch period, 45 students were asked to vote on the theme. The results were tabulated, and the theme with the most votes was declared the winner. 

Population: students at Madison High
Study: sample survey
Variable: theme (C)