This document discusses various data collection methods used in business research including censuses, surveys, observation, questionnaires, interviews, and case studies. It then focuses on experimental methods, defining independent, dependent, and controlled variables. An experiment aims to test one variable at a time in a fair, unbiased manner by manipulating the independent variable and measuring its effect on the dependent variable while controlling other outside factors. Examples are given of experiments involving puzzle completion times, water temperature at different depths, and taste preferences with varying sugar levels.

1. DATA COLLECTION
METHODS
Presentation by : ENHT 07
Abhilashini, Chathura, Croos, Dhanusha, Hema,
Madhusha, Niroshini, Sajith, Sanjaya, Shehani, Udari

2. Data Collection Methods
• In business research, data is collected from
various sources and a variety of methods are
used in its collection.
• Some of these methods are:
– Census or Surveys
– Observation
– Questionnaires and Interviews
– Case Studies
– Experiments

6. Experimental Method
• The experimental method involves
manipulating one variable to determine if
changes in one variable cause changes in
another variable.

7. Variables?
• A variable is anything in an experiment that
can change or vary.
• There are 3 kinds of variables:
– Independent Variable
– Dependent variable
– Controlled Variables or Controlled Environment

8. Characteristics of An Experiment
• Test one variable at a time.
• Must be fair and unbiased.
• Does not allow any out side factor to affect
the final out come
• Is a valid test. (proving a hypothesis)
• Has repeated trials. (minimizing outcome
errors)

9. Merits of Experimentation
• The biggest advantage of the experimental
method is it's unique ability to isolate causal
factors, since an experiment is highly
controlled.
• This method promises more accuracy in the
study.
• Reliable data can be collected.
• This is more suitable to the problem with
heterogeneous (varied) influencing factors.

10. Demerits of Experimentation
• The disadvantage is that exactly this control
may distort the validity of the obtained
results, and especially the ecological validity.
• This is very costly method.
• This is suitable to Simple problems with
limited scope.
• This is a time consuming method.

11. Situation 01
• Students were given the same jigsaw puzzle to
put together and they were timed.
– Independent Variable
• Ages of Students
– Dependent Variable
• Time taken to put the puzzle together
– Controlled variable
• Every one is given the same puzzle

12. Situation 02
• The temperature of water was measured at
different depths of a pond
– Independent Variable
• Depths of the water
– Dependent Variable
• Temperature
– Controlled variable
• Same pond, Same thermometer

13. Situation 03
• The taste of a plain tea was tested by using
different levels amounts of sugar.
– Independent Variable
• Level of sugar
– Dependent Variable
• Taste
– Controlled Variable
• Same Cup, Same sugar brand, same tea leaves, same
temperature level of hot water

14. Sources :
• Lightfoot, Cole & Cole (2008). The
development of children.
• Lilienfeld (2011). Psychology: from inquiry to
understanding.
• http://www.extension.org/pages/67849/expe
rimental-design#.U22yAvmSwro
• Wikipedia.com