Specify how you want the data to be accumulated within each time interval. Accumulation combines data within the same time interval into a summary value for that time period. Accumulation can be used in the following situations:
Let be the data vector ordered by the time series occurrence in the data set with respect to the observation index. Let
be the index that represents this ordering. Let QN be
the number of nonmissing values and let
be the number of missing values in the data vector.
Let
be the average value of the data vector with the
missing values ignored.
The following example
accumulates the observation series to the time series
, for
. In this situation,
and
for
.
Let be this accumulated value for this data vector when the following accumulationeither of two processes that are used to convert a time series. (1) Accumulation converts
a time series that has no fixed interval into a time series that does have a fixed
interval (such as hourly or monthly). (2) Accumulation converts a time series that
has a fixed interval into a time series with a lower frequency time interval (such
as hourly into daily). Accumulation combines data within the same time interval into
a summary value for that time period. methods are applied:
accumulates the vector values based on the average of their values.
Missing values are ignored
in the summation. If , then a is set to missing.
accumulates the vector values based on their corrected sum of squares.
Missing values are ignored
in the summation. If , then a is set to missing.
accumulates the vector values based on the maximum of their values.
Missing values are ignored
in the summation. If , then a is set to missing.
accumulates the vector values based on the minimum of their values.
Missing values are ignored
in the summation. If , then a is set to missing.
accumulates the vector values based on the number of nonmissing values.
accumulates the vector values based on the number of missing values.
accumulates the vector values based on their standard deviation.
Missing values are ignored
in the summation. If , then a is set to missing.
accumulates the vector values based on the summation of their values.
Missing values are ignored
in the summation. If , then a is set to missing.
accumulates the vector values based on their uncorrected sum of squares.
Missing values are ignored
in the summation. If , then a is set to missing.