Experimental method

• What is an experimental method?

  Involves the manipulation of an independent variable to measure the effect on the dependent variable.

  Experiments may be lab, field, natural or quasi.
• What is an aim?

  A general statement of what the researchers intends to investigate, the purpose of the study.
• What is an hypothesis?

  A clear, precise, testable statement that states the relationship between the variables to be investigated. Stated at the outset of any study.
• What is a directional hypothesis?

  States the direction of the difference or relationship.
• What is non-directional hypothesis?

  Does not state the direction of the difference or relationship.
• What are variables?

  Any ‘thing’ that can vary or change within an investigation. Variables are generally used in experiments to determine if change in one thing result to change to another.
• what are independent variables?

  Some aspect of the experimental situation that is manipulated by the researcher- or changes naturally- so the effect on the DV can be measured.
• What are the dependent variables?

  The variable that is measured by the researchers. Any effect on the DV should be caused by the change in the IV.
• What is operationalisation?

  Clearly defining variables in terms of how they can be measured.
• what is an example of an aim?

  To investigate whether animals improve a persons mood or day after feeling lost or hopeless.
• What is an example of an hypothesis?

  Drinking speedup causes people to become more talkative.
• What is an example of directional hypothesis?

  People who drink speedup become more talkative than people who don’t.
• What is an example of a non-directional hypothesis/

  People who drink speedup differ in terms of talkativeness compared with people who don’t drink speedup.
• What is an example of an experimental method?

  Gathering two groups of people.

  Then giving the first group a can of the Speedup drink. In the second group giving them a glass of water each.

  Then record how many words each participants say in a five-minute period immediately after having their drink.
• How to determine how to decide which type of hypothesis to use:

  Tend to use directional hypothesis when a theory or the findings of previous research studies suggest a particular outcome.

  When there is no theory or previous research or findings from earlier studies are contradictory, researchers instead decide to use a non-directional hypothesis.

  Even though speedup is a new energy drink, the effects of caffeine and sugar on talkativeness are well-documented. Therefore we will opt for a directional hypothesis.
• How do you test the effect of the IV?

  you need a experimental conditions. You need a comparison.

  so you either for example,

  compare peoples talkativeness before and after drinking speedup.

  compare the two groups of participants.
• What is an example of an operationalised hypothesis?

  After drinking 300ml of speedup, participants say more words in the next five minutes than participants who drink 300ml of water.