Create the "Price Observation Table"

valid_pot in OECDsppps creates the "Price Observation Table" containing a characterisation o f the individual product as well as two individual price outlier statistics: the Ratio-to-average price test and the t-value test; see World Bank (2013) , table 9.1a. All price quotes that do not pass the two tests are flagged in columns Ratio-to-average price test FLAG and T-value test FLAG, respectively.

Usage

valid_pot(
  df,
  Year = "Year",
  `Product code` = "Product code",
  `Product description` = "Product description",
  `Reference quantity` = "Reference quantity",
  `Unit of reference quantity` = "Unit of reference quantity",
  `Date of quote` = "Date of quote",
  Region = "Region",
  `Shop identifier` = "Shop identifier",
  `Type of shop` = "Type of shop",
  `Quantity observed` = "Quantity observed",
  `Unit of observed quantity` = "Unit of observed quantity",
  `Price observed` = "Price observed",
  `Reference quantity price` = "Reference quantity price"
)

Arguments

df

add

Year

add

`Product

description` add

`Date

of quote` add

`Shop

identifier` add

`Type

of shop` add

`Quantity

observed` add

`Unit

of observed quantity` add

`Price

observed` add

`Reference

quantity price` add

`Region`

add

Details

The probability density function of a normal distribution is given by \[f(x) = \frac{1}{\sqrt{2\pi} \sigma} e^{-\frac{1}{2}\left(\frac{x-\mu}{\sigma}\right)^2},\] where \(\mu\) denotes the mean of the distribution and \(\sigma\) its standard deviation.

References

World Bank (2013). Measuring the Real Size of the World Economy: The Framework, Methodology, and Results of the International Comparison Program — ICP. World Bank, Washington DC. ISBN 978-0-8213-9731-2, doi:10.1596/978-0-8213-9728-2 .