research issues

• Extraneous variables:

  It is the type of any variable apart from the independent variable that can affect the dependent variable if it is not controlled.  These variables do not differ systematically. Examples of this could be the age of  the participants and the lighting of the laboratory where the test is taking place.
• Confounding variables differ systematically with the independent variables, which makes it difficult to control the confounding variables. An example of this would be if an exciting event has happened before arriving so you would not be able to tell if the talkativeness is because of the excitement or because of the energy drunk so it makes it difficult to measure the dependent variable.
• Demand characteristics are any type of cue for the researcher that the participants can interpret, such as the researcher revealing what the investigation is going to measure and this can lead to the participants changing their behaviour to what is best suited for the experiment so the researcher is able to get the results they wanted which can make it difficult to tell if the results are because of this.