Scope of Research RESEARCH METHODOLOGY
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b. HeteroscedasticityTest Heteroscedasticity test aims to test whether in the regression model
there is unequality variance from one residual observation to other observation. If the variance from one residual observation to another
observation is fixed, then it is called homokedastitas and if it is different called heteroscedasticity. A good regression model is a
regression model that is homokedastitas. Detection the presence ofheteroscedasticitycan be do by looking at whether there are a
particular pattern in scatterplot graph between the predictive value of the dependent variable ZPRED with the residual SRESID where
the Y axis is the predicted while X is residual. If there are certain patterns so that will indicate there has been heterokedestitas, but if
there is no clear pattern and the points spread above and below zero on the Y axis, so it heteroscedasticity does not happen Ghozali,
2011:105. c. Normality test
Normality test data aims to test whether the regression model, both independent and dependent variables, have been distributed normally.
Good regression models is regression model with normal distribution data or near normal. To determinewhether or not the normal
distribution of the data can be detected by looking Normality Probability Plot P-Plot. If the data dots spread around the diagonal
line and follow the direction of the diagonal line or line histogram,
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then showed a normal distribution pattern and regression models have met the assumptions of normality Ghozali, 2011:149.