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2. Data Quality Test
To get good results then before the statistical test, data must to be tested using validity and reliability.
a. Validity Test
. Validity is a characteristic of measurement concerned with the
extent that a testmeasures what the researcher actually wishes tool reflect true differences among participantsdrawn from a
population Donald Cooper, 2006:765. According to Imam Ghozali Ghozali, 2005:45 the validity of
this research is used to measure the legality of a questionnaire. Test validity used to measure the legal valid or unvalid of a
questionnaire. A questionnaire is said valid if the questions on the questionnaire is able to reveal something that will be on the
questionnaire measure. The total score on test validity of said valid if the number of scores 0.30 sugiono, 2007 : 178.
b. Reliability Test.
Reliability is a characteristic of measurement concerned with accuracy, precision, andconsistency ; a necessary but not
sufficient condition for validity if the measure is notreliable, it cannot be valid . Reliability is concerned with estimates of
the degree to which ameasurement is free a random or unstable error Donald Cooper, 2006:352
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Reliability refers to the extent to which a scale produces consistent results if repeated measurements are made.
Therefore, reliability can be defined as the extent to which measures are free from random error Maholtra, 2006: 273.
According to Imam Ghozali Ghozali, 2005:42 reliability measurements can be done in 2 ways:
1. Measure or measurements repeated: here someone will be
given the same questions at different times, and then see if he remains consistent with the answers.
2. One shot or one-time measurement: here measurement only
once and then the results werecompared with another question or measure the correlation between answers to questions. SPSS
provides facilities to measure the reliability with statistical uni Cronbach alpha α. A construct or variable is said cronbach
reliable if the value of alpha 0.60. As a gauge that shows consistency of the measuring instrument
to measure the same phenomenon in other occasions. to look at reliability, the calculated alpha cronbach each - each
instrument. Variable cronbach alpha has a value greater than 0.60 Imam Ghozali, 2005:42
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3. Classic Assumption Test
a. Normality Test
Testing normality is a test of the normality of data distribution. Test is a test of the most widely performed by parametric
statistical analysis. The use of normality tests becausethere is a parametric statistical analysis, the assumptionsthat must be owned
by data is that the data are normally distributed Ghozali, 2005:110.
The purpose normally distributed data is that data will follow a normal distribution form. There are two ways to detect whether or
not residual normal distribution, those are with graph analysis and statistical tests. One of the easiest ways to see the normality of
residuals is to look at a histogram graph comparing observational data with the distribution of near-normal distribution. Normal
distribution will create a straight line diagonal and plotting residual data will be compared with the diagonal line. If the
residual data distribution is normal, then the line that describes the actual data will follow the diagonal line. Normalitytest used
whether the regression model contained in a normal distribution or not between dependent and independent variables. In this
research, the normality test using normal p-p plot histogram chart Ghozali, 2005:110.
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