RPICPI User Group

last person joined: one month ago 

To foster co-operation and the exchange of information between the ONS, its advisory bodies and other users. Please see 'Aims of the RPI/CPI User Group' in the library for further details.

An item should never be removed from the price sample because it is seasonally disappearing

  • 1.  An item should never be removed from the price sample because it is seasonally disappearing

    Posted 21-03-2018 03:20
    Dear all:

    I noticed that the article by Phil Gooding, "Consumer price inflation basket of goods and services: 2018", mentioned on p. 9 under removals:  "peaches and nectarines have been replaced by raspberries with the aim of improving the measurement of fruit prices overall. As already mentioned, the change rebalances the fruit items from stoned fruits – which continue to be represented by plums and avocados – to soft fruits. The peaches and nectarines item was chosen for removal because its availability varies so much across the seasons that prices were only collected for eight months of the year. It was one of the small number of items in the baskets collected on a seasonal basis."
    It does not seem to me that whether an item is seasonally disappearing or not should have any bearing on its removal from the list of priced items. Would a different determination have been made as to a stoned fruit to be dropped if this were not a consideration? The seasonal imputation procedure now used by the ONS, mandated by Eurostat, is a poor way of handling seasonally disappearing items, and should be reformed. If the ONS is unhappy with the current Eurostat-mandated imputation procedure for handling seasonally disappearing items, as it should be, it should replace it with something better. It shouldn't just try to minimize the damage done by making this attribute a criterion for removing an item from the price sample.
    Did industry demand in any way influence the decision to replace peaches and nectarines with raspberries in the price sample? The UK is an important producer of raspberries, but not so much of peaches and nectarines.

    Best regards,

    Andrew





  • 2.  RE: An item should never be removed from the price sample because it is seasonally disappearing

    Posted 22-03-2018 08:45

    Each item in the basket should be regarded as representing either itself or a group of very similar items.  While technically an avocado is a fruit, it can scarcely be regarded as so similar to peaches or nectarines, from the average consumer's viewpoint, that it can be regarded as representing them.  Thus plums are now effectively representing all stoned fruit.


    There is of course plenty of precedent for having items in the basket that are regarded as unavailable at certain times of the year.  Nobody would suggest removing all such items.