Time Series Analysis(英文版)(ppt 37頁)

Time Series Analysis(英文版)目錄：
一、 What is Time Series Analysis?
二、 How are Time Series plots developed?
三、 What are the advantages of Time Series Analysis?
四、 What are Time Series used for?

Time Series Analysis(英文版)內容提要：
Advantages of Time Series：
If the time series shows a relative smooth pattern from one year to the next … the trend and the year over year growth would provide roughly the same reading.
But, if there was a significant market event or change, the year over year trends will be misleading
……

Underlying Trend：
Underlying trend is a trend line that best describes the current sales growth rate.
It is the collective representation of all underlying factors that are influencing sales… industry, competition, and company specific, etc.
It is determined using a best-fit line to a set of points on the time series. The points are selected based on in-depth understanding of the underlying factors influencing sales, how they have changed over time, and how they will likely change in the future.
Points of inflection on the time series often signal changes in the underlying factors and hence the underlying trend.

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