One draw back to the control of history effects uising this method of time series is that: The comparison group may not be equivalent to the treatment group.
This is a study that is done through the use of data that has been measured and collected over a period of time.
The time series study is one that has well defined data and shows fluctuations as they happen over the years.
Read more on time series here: https://brainly.com/question/20344588
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