Machine Learning Model Validation (Aijun Zhang 2024).pdf
Rao 2a analytics 1 availability & deficits
1. FOOD SECURITY
Concepts, Basic Facts,
and Measurement Issues
June 26 to July 7, 2006
Dhaka, Bangladesh
2. Rao 2a:
Analytics 1: Food Availability
and Food Deficits
Learning: Based on the concepts of the
basics of the aggregative models and of the
different types of food deficit, trainees will
develop facility with graphical
representations in the analysis of any given
real-life situation.
3. Brief Contents
• three analytical approaches relating to
availability, access and nutrition
• an aggregative model of the basics:
requirements, demand and supply
• three types of deficit: production deficit, supply
deficit, demand deficit
• market imbalances versus food deficits
• graphical representation of the basics and of
deficits
4. Analytic Approaches
• Food Availability Approach
– Aggregate Level
– Key Concepts: Production, Supply, and types of
Food Deficit
• Food Access Approach
– (Mainly) Individual or HH Level
– Key Concepts: Economic and Social
Access, Effective demands or Entitlements
• Food Utilization Approach
– (Mainly) Individual or HH Level
– Concepts: Nutrition, Health, and valued or
functional Outcomes
5. Factors Determining
Food Availability
• the volume and stability of food production
(whether subsistence or market oriented)
• available food stocks (farm-
level, commercial, government stocks)
• food imports (commercial and concessional).
6. Factors Determining Access to Food
• For the market-dependent: the purchasing
power, or level of real income
– At HH Level: wage levels, employment, prices, etc.
– At National Level: availability of F/E for food
imports
• For subsistence producers: productive assets
available & non market transfers
– [At National Level: resource endowments & food
aid respectively)
7. Factors Determining
Utilisation of Food
• Basic (physical) Factors
– Dietary intake
– Body metabolism
• Complementary (socio-environmental) Factors
– Water, sanitation and food safety
– Health care, disease prevention and control
– Education and awareness of food-nutrition factors
– Food culture and food norms
8. An Aggregative Model
of Food Deficits
• To analyze FS of a country (both at point in
time and changes over time) we use the
following REQUIREMENTS--DEMAND--
SUPPLY graphs
9. Fig. 2.1: Closed Economy Case
(w/ neither food imports nor exports)
• Basic model of aggregate food situation in closed economy
Note: real economies will be neither completely closed nor completely open
10. Fig. 2.2: Open Economy w/ Imports
• Basic model of aggregate food situation in open economy
Note: real economies will be neither completely closed nor completely open
11. 5 Basic Elements of the Model
• 1. Production Curve
– shows the volume of aggregate food production at
varying market prices of food
– food production includes subsistence production
as well as production for sale on the market
12. 5 Basic Elements of the Model
• 2. Supply Curve
– shows total food supplies at varying market prices;
incorporates food production (see
previous), modified by stock changes and food
imports/exports.
– For a closed economy with NO stock
changes, Supply Curve = Production Curve
– For open economy, this is so only until domestic
price reaches world price level
13. 5 Basic Elements of the Model
• 3. Demand Curve
– shows total food demand (effective market
demand plus home consumption from subsistence
output)
– Why negative slope? Real income effects.
• 4. Food Requirements
– approximately given by calorie or staple food
requirements on the basis of food balance sheets
– IMP. NOTE: more unequal is food
distribution, higher will be requirements
14. 5 Basic Elements of the Model
• 5. Market Prices
– major factor determining food production, supply
and demand.
– In closed economy, regulated OR competitive OR
quasi-competitive
– In a free, open economy: price is world-market
determined (CIF or FOB)
15. Food Deficits
• The following types of food deficits can arise:
– in PRODUCTION
– in SUPPLY
– in DEMAND
– MARKET IMBALANCES (deficit or surplus)
16. Types of Food Deficit (defined)
A production
A supply A demand
[or structural]
deficit deficit
deficit
production supplies
there are people
insufficient to (prod.+Δstocks+
without effective
meet total food {M-E}) less than
market demand.
requirements requirements
FP < FR [does
FS < FR FD < FR
not necessarily
[necessarily [necessarily
mean FIS
implies FIS] implies FIS]
e.g., Japan]
NOTE: A
demand deficit is
the result of
poverty.
17. Types of Food Deficit (graphs)
2.3a: Areas of production deficits
(& supply deficits in a closed economy)
•
18. Types of Food Deficit (graphs)
2.3b: Area of supply deficits
in an open economy
•
19. Types of Food Deficit (graphs)
2.3c: Area of demand deficits
•
20. Types of Food Deficit (graphs)
2.3d: Areas of market imbalances (surpluses & deficits)
in a closed economy
•
21. Market Imbalances
• Market imbalances (deficits or surpluses)
– ←→ market price differs from equilibrium price
– [set below (market supply deficit) or above (market demand
deficit) "market-clearing" P]
• Question: Is this statement true?
If the market price is fixed below equilibrium price … food demand
would rise, so demand deficit would diminish.
However, food supplies from domestic production as well as
food imports (in the open economy case) would go down.
• Market imbalances either require Government
Regulation or Market Collusion.
22. Table 2.1: Types of Food Deficits
Type of deficit Definition Examples referring to
Closed Open
economy economy
Production deficit food production < food requirements R-A R-C
Total supply deficit total food supplies < food requirements R-A R-B
Demand deficit effective demand < food requirements R-A R-B
Import deficit market production < effective demand - B-C
Market imbalances:* IF market prices are set:*
- Market (-supply) market supplies < effective demand below po above pm
deficit
- Market surpluses market supplies > effective demand above po below pm
* Prices set apart from equilibrium prices lead to an overall change of the deficit structure, see above.