BUSINESS ADMINISTRATION
BUSINESS ANALYTICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following is not true of a stationary time series?
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The process generating the data has a constant mean.
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The time series plot is a straight line.
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The statistical properties are independent of time.
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The variability is constant over time.
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Explanation:
Detailed explanation-1: -The mean of the residuals is always zero.
Detailed explanation-2: -variance is NOT a time series component, it refers to the spread of a data set.
Detailed explanation-3: -A common assumption in many time series techniques is that the data are stationary. A stationary process has the property that the mean, variance and autocorrelation structure do not change over time.
Detailed explanation-4: -A stationary time series is one whose properties do not depend on the time at which the series is observed. Thus, time series with trends, or with seasonality, are not stationary-the trend and seasonality will affect the value of the time series at different times.
There is 1 question to complete.