X11/Y2K Census Method II Monthly

Provides a full-featured implementation of the US Bureau of the Census X-11 variant of the Census method II seasonal adjustment procedure. The arrangement of options follows closely the definitions and conventions described in the bureau of the Census documentation.

 Note that, unlike the Bureau of the Census implementation of this algorithm, the implementation in STATISTICA can handle dates past the year 2000.

Element Name Description
General
Input already adjusted If you select this option, STATISTICA assumes that the input is already a seasonally adjusted series. In that case, the X-11 procedure can be used to test for residual seasonality and trading-day variation by completing the standard steps in parts B and C of the computations (see X-11 section of the Electronic Manual for details).
Type of seasonality Specifies whether to compute the Additive or Multiplicative seasonal adjustment.
Start series at month Select the month for first observation, i.e., the start month (of the first year) for the input series.

 Note: You can enter either four-digit years in the range from 1901 through 2099, or two-digit years in the range from 0 through 99. If you specify a two-digit year less than 20, the respective year will be interpreted as 20xx, where xx stands for the two-digit year (e.g., 11 will be interpreted as 2011); if you specify a two-digit year greater than or equal to 20, then the year will be interpreted as 19xx, where xx stands for the two-digit year (e.g., 55 will be interpreted as 1955).
Start series at year Select the year for first observation, i.e., the start year (of the first month) for the input series.

 Note: You can enter either four-digit years in the range from 1901 through 2099, or two-digit years in the range from 0 through 99. If you specify a two-digit year less than 20, the respective year will be interpreted as 20xx, where xx stands for the two-digit year (e.g., 11 will be interpreted as 2011); if you specify a two-digit year greater than or equal to 20, then the year will be interpreted as 19xx, where xx stands for the two-digit year (e.g., 55 will be interpreted as 1955).
Length-of-month allowance When this option is selected (set to True), the differences in the lengths of different months (30-day months, 31-day months, and the month of February) are not used to adjust the daily weights. Consequently, the variability arising from differences in the lengths of months will be included in the trading-day factors. Note that this option is only available (and meaningful) if Trading day regression & adjustment is requested, and when Multiplicative adjustment is requested (see above).
Detail of reports Select the number of X-11 results tables to be computed and reported.
Detail of graphs Select the detail of graphical results computed for the X-11 analysis.
Generates data source, if N for input less than Generates a data source for further analyses with other Data Miner nodes if the input data source has fewer than k observations, as specified in this edit field; note that parameter k (number of observations) will be evaluated against the number of observations in the input data source, not the number of valid or selected observations.
Trading Day Regression
Trading day regression Specifies whether and how a least-squares trading-day adjustment will be included in the analysis. Different months consist of different numbers of trading-days (i.e., Mondays, Tuesdays, etc.), which can greatly affect the monthly values.
Start estimation at year If trading-day regression is requested, determine which years of the input series are used to compute the trading-day weights (by default all years), and to which years they are applied (by default to all years).

 You can enter either four-digit years in the range from 1901 through 2099, or two-digit years in the range from 0 through 99. If you specify a two-digit year less than 20, the respective year will be interpreted as 20xx, where xx stands for the two-digit year (e.g., 11 will be interpreted as 2011); if you specify a two-digit year greater than or equal to 20, then the year will be interpreted as 19xx, where xx stands for the two-digit year (e.g., 55 will be interpreted as 1955).
Adjust beginning at year If trading-day regression is requested, determine which years of the input series are used to compute the trading-day weights (by default all years), and to which years they are applied (by default to all years).

 You can enter either four-digit years in the range from 1901 through 2099, or two-digit years in the range from 0 through 99. If you specify a two-digit year less than 20, the respective year will be interpreted as 20xx, where xx stands for the two-digit year (e.g., 11 will be interpreted as 2011); if you specify a two-digit year greater than or equal to 20, then the year will be interpreted as 19xx, where xx stands for the two-digit year (e.g., 55 will be interpreted as 1955).
Sigma limits for extremes If trading-day regression is requested, then the value specified for the Sigma limit for excluding extreme determines how outliers in the irregular component are to be treated. Specifically, all irregular values are excluded from the computations if they deviate from 0 (additive model) or 1 (multiplicative model) by more than x * s [where x is the value entered and s (Sigma) is the estimate of the trading-day standard deviation].
Graduating Extremes
Sigma limits, full weight The Full weight value determines the multiple of s (Sigma; the estimate of the trend-cycle standard deviation) below which a value will be assigned a full weight.
Sigma limits, zero weight The Zero weight value determines the multiple of s above which a zero weight will be assigned. Between these two cut-off values, linearly graduated weights are assigned.
Missing Data
Replace missing data Specifies how missing data is to be replaced. Missing data can be replaced by the overall mean, interpolated from adjacent points, replaced by the mean or median of N adjacent points (on both sides of the hole), or estimated (predicted) from linear trend regression.

 Note that as long as the missing data are at the end of the series (trailing missing data) or the beginning of the series (leading missing data), the missing data will simply be ignored.
Number of adjacent points Applicable if missing data are replaced by the mean or median of N adjacent points; specify N.

 The missing data are replaced by the mean or median computed from the N adjacent points on both sides of the hole of missing data.