这边看，这边瞧
If you do much data analysis it won’t be long before you work with data measured over a range of times. When you do see time-series data, you’ll find that time scales and time units have some very quirky properties.
如果您要进行大量数据分析，那么很快就可以处理经过一段时间测量的数据。 当您看到时间序列数据时，您会发现时间刻度和时间单位具有一些非常古怪的属性。
一次又一次 (Time after Time)
You might think that time is measured on a ratio scale given its ever finer divisions (i.e., hours, minutes, seconds). Yet it doesn’t make sense to refer to a ratio of two times any more than the ratio of two location coordinates. The starting point is also arbitrary. So time clearly isn’t measured on a ratio scale but it can be measured on interval or ordinal scales. Time units are also used for durations, however durations can be measured on a ratio scale. Durations can be used in ratios and they have a starting point of zero, but no negative numbers.
您可能会认为时间是用比例尺来衡量的，因为它的划分越来越精细(例如，小时，分钟，秒)。 但是，引用比两个位置坐标的比率多两倍的比率是没有意义的。 起点也是任意的。 因此时间显然不是用比例尺来衡量的，而是可以用间隔或序数来衡量的。 时间单位也用于持续时间，但是持续时间可以按比例尺进行测量。 持续时间可以按比例使用，并且起点为零，但没有负数。
Time measurements can be linear or cyclic. Year is linear, and can be measured on either an interval scale or an ordinal scale. For example, the year 1953 can be expressed as an integer (ordinal scale) or a decimal (interval scale). Furthermore, all values of linear time are unique. The year 1953 happened once and will never recur. Linear time is like a river. You start at some point and go with the flow. You can’t get back to your starting point, but it still exists somewhere in time.
时间测量可以是线性的也可以是循环的。 Year是线性的，可以间隔间隔或序数尺度进行度量。 例如，1953年可以表示为整数(常规比例)或十进制(间隔比例)。 此外，线性时间的所有值都是唯一的。 1953年发生过一次，将永远不会再发生。 线性时间就像一条河。 您从某个点开始，然后顺其自然。 您无法回到起点，但它仍然存在于某个时间。
Some time scales repeat. If day one is a Monday, then so is day eight. Likewise, month one is the same as month thirteen. So time can also be treated as being measured on a repeating ordinal scale. Durations don’t repeat; one day isn’t the same as eight days.
重复一些时间尺度。 如果第一天是星期一，那么第八天也是如此。 同样，第一个月与十三个月相同。 因此，也可以将时间视为按重复序数尺度进行测量。 持续时间不重复； 一天不等于八天。
