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Identify the basic elements of an experiment. Discuss how using a control group in an experiment allows the researcher to make causal interpretations.

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Introduction

Identify the basic elements of an experiment. Discuss how using a control group in an experiment allows the researcher to make causal interpretations. Experimentation is a research method which enables psychologists to test for a hypothesis. This essay will define the basic elements of an experiment and to discuss how using a control group in an experiment allows researcher to make causal interpretations. Psychological experiment is data collection which helps researcher to recognize the stimulus- response relationship. Experiment proceeds under experimental conditions following the statements of hypothesis. A hypothesis is a predicted relationship between variables and a tentative solution to researchers' problems (Mcguigan, 1993). ...read more.

Middle

Since data collected indicates the true or false probability of hypothesis, extraneous variable must be eliminated or regulated by a control group. Independent variable is controlled when varied in a known and specified manner. Typically, participants are assigned to 2 groups: experimental group and control group by randomization. This balances conditions of the 2 groups, letting them approximately equivalent (Mcguigan, 1993). The experimental group exposed to experimental treatment whilst control group exposed to normal treatment. The difference between is the specific value of independent variable. Thus, effects of the experimental treatment are evaluated. A control group ensures consistence of stimulus characteristics so responses can carefully measured (Martin, 1996). ...read more.

Conclusion

A new drug study can demonstrate how control group, together with double-blind procedure enhance experimental accuracy. A placebo is presented to control group in this experiment. Giving a placebo produces an effect of ingestion of a therapeutic substance (Liebert, 1995). As the placebo has no real healing power on the control group, the experimenters can deduce whether the new drug is efficient. The basic elements of an experiment are the environmental conditions following the hypothesis, independent and dependent variable, application of control group and double-blind procedure. The comparison between control group and experimental group allows researcher to make causal interpretations accurately as extraneous variable is eliminated, no variables but only independent variable tested is affecting the dependent variable. Total words: 491(exc. reference) ...read more.

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