Show R rate measure of the intensity of the occurrence of an event For example the mortality rate equals the number who die in one year divided by the number at risk of dying Rates are usually expressed usingstandard denominator such as000 or 100 000 persons regression analy Regression analysis istool used by economists and others to estimate the relationships amongdependent variableand one or many independent variable The purpose of regression analysis the best fit data points fromstraight line down on an XY graph relative risk The rate of disease in one group exposed to particular factor g toxic spil divided by the rate in another group which is not exposed relative risk of one indicates that the two groups have the same rate of disease risk or risk factor Risk isterm used by epidemiologists to quantify the likelihood that something will oceur risk factor is something which either increases or decreases an individualrisk of developingdisease However it does not mean that if exposed an individual will definitely contract particular disease standard error In statistics the standard error is defined as the standard deviation of an estimate That is multiple measurements ofgiven value will generally group around the mean or average value innormal distribution The shape of this distribution is known as the standard error survey An investigation in which information is systematically collected population survey may be conducted by face-to-face inquiry by sel-completed questionnaires by telephone by postal service or in some other way Each method has its advantages and disadvantages The generalizability of results depends upon the extent to which those surveyed are representative of the entire population type error Also known as false positive or alpha error An incorrect judgment or conclusion that occurs between when variables an association where in is found fact no association exists In an experiment for example if the experimental procedure does not really have any effect chance or random error may cause the researcher to conclude that the experimental procedure did have an type Il error Also known as false negative or beta error An incorrect judgement or conclusion that occurs when no association is found between variables where in fact an association does exist Inmedical screening for example negative test result may occur by chance insubject who possesses the attribute for which the test is conducted effect Digital image 2005 Marriott Library University of Utah Al rights reserved |