Question

What are independent variables, dependent variables, and extraneous variables. Describe two ways that researchers attempt to control extraneous variables.

Answer 1

Research is a studions inquiry or examination investigation , or experimentation' aimed at the discovery & interpretation of facts a revision of accepted theories or laws in the light of new facts or practical applications of such new or revised theories of laws (webster) → Variables : something that vasies Specifically variables represents persons or objects that can be manipulated , controlled or merely measured for the sake of research. is Independent variable le cause) These variables are intention ally changed to observed its effect on the dependent variable These are ones that are more or less controlled 117 Dependent variable: live effect) These are not controlled or manipulated variables in any way, but instead are simply measured

or registered. It is the event studied & expected to change when the independent variable is changed y example: id scientist studies the impact of a drug on cancer. (Lv) independent variable: e0d ministration of the dry (DV) Dependent variable impact of drug has on cancer Siis extraneo no variable : Any variable other than the independent variable that could have an influence on the dependent variable example: extraneous variables for a test on alcohol & driving performance (weather, distractions, road condition, driving experience)

como-2 Two ways that researchers attempt to control extrancous variables: → Extranuous variables are a challenge to both external & internal validity of the experiment ? Randomization : It is a statistical procedure by which the participants are allocated into groups usually called Study & control groups to recieve or not to recieve an experimental preventive or therapeutic procedure , manoeuvre or intervention It is an attempt to eliminate bias & allow for comparability by matching Randomization is the heart of a control trial It gives the greatest confidence that the groups are comparable so that like can be compared with like. It ensures that investigator has no control over allocation of participants to either study or control group, this climinating what is known as selection bias . - Bu yandom allocation every individual gets an equal chance of being allocated into either group or any of the trial groups.

127 Use of experimental design: Experimental design is the organisation of participants into the research conditions The experimental design play a crucial role in reducing or completely removing the role & impact of the extraneous Variable It uses manipulation & controlled testing to understand causal process. One or more Variables are manipulated to determine their effect on a dependent variable. it ensures results are valid , easily interpreted & definitive