can the ljung-box test be used to test the validity of a time series? what type of test measures time series is the ljung test accurate can a time series be used for a regression test? how to tell if a period is constant what statistical tests to do for trend how is ljung test used how does the ljung test for the variability of the time series work? can a time series always go up or down how to find if a time series is continuous what is the ljung test for the data how are time series measured in a laboratory setting how can i measure a time series can the ljung-box test test for trend? how to test the validity of longitudinal data how to measure a time series for a sample how to determine time series of variables what statistical test to use to test time series what tests do you need for measuring trend how to interpret data to find a trend