Lie detector tests or polygraph tests as they are often referred to as are not something new- they have been there since decades ago. Similarly you need to pass a polygraph test before getting a job at the FBI, CIA or other government organizations. The polygraph is the machine used for such a test where it measures several physiological parameters such as blood pressure, pulse, respiration and skin conductivity while the subject is answering the different questions.
The general concept behind this test is that a tested subject that lies with their answers to the questions will produce physiological responses that are easily differentiated from responses due to non-deceptive answers. There are about 4 to 6 sensors that are attached to the subject. The machine then records the several signals that are intercepted by these sensors on a "graph". So how do this lie detector tests work? The website at www.liedetectortest.uk will definitely be able to answer all your questions.
The examiner will start by conducting a pre-test interview to get some information that would be used to create diagnostic questions later. He or she will then inform the subject on the working of the polygraph machine and insist on why the subject must answer each and every question with the absolute truth. Afterwards the subject is asked by the tester to deliberately lie. The tester will report that he was able to detect the lie in the machine.
After a subject hears that the lie was detected he becomes anxious as he knows of the test's validity. It is then that the real test now starts. The tester asks some different types of questions in alternate. These are the irrelevant questions, diagnostic questions and the relevant questions. An irrelevant question may be like "Is your name George"? The relevant questions or simply RQ are however the ones the tester is interested in. When you try the lie detector test uk you will definitely have the answers you need.
This technique is what is commonly referred to as the Control Question Technique (CQT). This method is generally known as the CQT (Control Question Technique).
Another alternative technique is the Guilty Knowledge Test (GKT) or Concealed Information Test (CIT). There is however another alternative method known as the Guilty Knowledge Test (GKT) or Concealed Information Test (CIT) that prevents the questioning style errors. The tester has no knowledge of the crime or the circumstances of the question. The questions asked are in multiple choices and the subject is rated on their reaction to the correct answer. It likely the subject knows the facts to the case when there is a stronger reaction to the guilty information.
For some time there have been arguments on the effectiveness and relevance of polygraph tests. What is for sure though is that lie detector tests have been conducted in quite a number of instances.