Volume 14, Issue 2, June 2016, Pages 133–139
Open Access
- National Agrarian University of Amenia, 0009, Yerevan, St. Teryan 74, Armenia
- Received 2 February 2016, Accepted 3 May 2016, Available online 24 May 2016
- Open Access funded by Agricultural University of Georgia
- Under a Creative Commons license
Abstract
In
follow article quarterly seasonal fluctuations of the consumption of
fruits and vegetables in the food basket were studied in period of
2008–2015 by data of RA. Among the other products in food basket the
seasonal fluctuations of fruits and vegetables are more noticeable. The
main purpose of this research is to discompose the time series of
consumption volumes of fruits and vegetables for studying the seasonal
component's impact and for making the credible predictions. The tendency
of these commodities have been shown by the linear regression model.
According regression model the consumption value of fruits in the food
basket each quarter decreased increased by 1.741 AMD, the rest part of
the fruit consumption level is formed through the seasonal and error
components. According regression model, the consumption value of
vegetable in the food basket each quarter increased by 27.97 AMD, and
main part of the volume of vegetables consumption in the time series is
formed through the seasonal and error components. The seasonal
fluctuations of commodities of have been presented with the help of
multiplicative models. Taking account the main components of studied
time series, the predicted values of the consumption of fruits and
vegetables in the food basket have built for the further quarters.
Keywords
- Seasonal fluctuation;
- Fruits;
- Vegetables;
- Food basket;
- Additive model
Introduction
The
food basket actual volume is calculated by National Statistical Service
of Republic of Armenia by the data of the Integrated living conditions
Survey based on the methodology of World Bank. The food basket shows the
average volume of the products which are consumed by the adult person
during a month. It includes 12 named food products, and some of them
have permanent consumption, several products have seasonal consumption
per adult person. Among the products of food basket the consumption
fruits and vegetables are distinguished by noticeable seasonal
fluctuations. These fluctuations depends on not only their production
but also the socio - economic conditions of the country. In this point
of view the it's necessary to analyze time series of these products. In
this research the time series encompass the quarterly data 2008–2015.
Objectives and methods
The
objective of this research is to study the time series of consumption
volumes of fruits and vegetables in food basket and to analyze the
influence of separate components of time series.
It
is generally believed that time series are composed of four components:
trend, cyclicality, seasonality, and irregularity. Not all time series
data have all these components. The long-term general direction of data
is referred as trend. The cycles are patterns of highs and lows through
which data move over time periods usually of more than a year. Seasonal
effects on the other hand are shorter cycles, which usually occur in
time periods of less than one year [2].
One
of the methods presenting the seasonal characteristics of these
commodities is the evaluating the seasonal indices. The analysis of time
series, which include the seasonal waves, allows separately to study
the nature of seasonal fluctuations. The seasonal fluctuations are
describing by special indicators known as seasonal indices. They reflect
the seasonal waves of time series. For disclosing the seasonal
fluctuations usually the monthly or quarterly data are studied for
several years. At least three years' quarterly data are observed in
order to avoid the irregular affect of the one year [3].
