Scope Of Research Sampling Method
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According to Zulkifli Matondang, 2009, normality test is conducted in purpose to detect whether a set of data will be used as
basic start to test hypothesis is empirical data that meets the naturalistic nature. Naturalistic nature is a thought that phenomena
symptoms occur in this nature are natural and patterned. Widhiarso said that normality tests are some tests to measure whether our set of
data having normality distribution so it can be used in parametric statistic. Tests of normality become important because this is a
parametric test and have to normal distributed Haryadi and Winda, 2011. So, normality tests are some kind of tests to clarify whether the
data obtained are normally distributed and, importantly, represent the whole population or not.
In this research, researcher will test the distribution of data by seeing Normal Probability Plot P-P Plot graph. Normal distribution
will form a diagonal straight line and plotting residual data will be compared with diagonal lines. The distribution of residual the data is
normal, if the line that describes the actual data follow the diagonal
line Ghozali, 2009:149. b.
Multicollinearity Test
Multicollinearity test aims to test whether the regression model found a correlation between the independent variables Ghozali,
2009:95. A good regression model should not happen correlation between the independent variables. To detect the presence or absence
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of multicollinearity in the regression model can be seen from the value of tolerance and the variance inflation factor opponent VIF.
Multicollinearity views of the tolerance value 0.10 or VIF 10. Both of these measurements indicate each independent variable which is
explained by the other independent variables.