Forecast Report with Analog Years-Kenya

Introduction

This is a forecast report. The goal is to assist users in evaluating current forecasts in the context of past forecasts and to translate the forecast component into key assumptions about food security.

The report includes the following key components:

1. A verbal summary of assumptions based on the statistics in this forecast [NOT UPDATED]

2. Mean Area, Production, and Yield over the years 2006 to 2016:This provides context for interpreting the grain data

3. Historical Out of Sample Forecast Error Averaged Over a 10 Year+ Period. We show the Mean Absolute Percent Error (MAPE).

4. Yield Forecast, (based on May 2022 Precip, NDVI, Et0 ) expressed as percent of mean yield over the period 2006 - 2016.

5. Forecasts and Forecast Error in Analog Years We show specific forecasts and forecast error for years when the climate patterns are similar to what is expected in the current season.

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Summary Figures

Mean area, production, and yields for the years 2006 to 2016.

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Out of Sample Forecast Error (MAPE)

Mean Absolute Percent Error (MAPE) calculated based on historical out of sample seasonal forecasts. Lower scores indicate greater accuracy. Forecasts are based on model type MODEL¹

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Yield Forecast for May 2022

Forecast values expressed as percent of Mean Yields over the Years 2006 - 2016.

The figure shows predicted percent of mean (center) as well as lower (left) and higher (right) predicted percent of mean intervals.

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Static and Dynamic Version of Main Forecast

Roll over the polygon borders to get the district name and % of mean forecast value.

Static Version

This map shows the main % of mean forecast value along with district lables for reference.

This table shows the forecast percentage of mean values in the above table along with the mean yield values from the first figure.

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Table of Mean Yields and Predicted Percent of Mean Values

District	% of mean
Tana River	99
Lamu	83
Tharaka Nithi	71
Machakos	47
Makueni	27
Nyandarua	55
Nyeri	75
Kiambu	25
West Pokot	63
Trans Nzoia	90
Uasin Gishu	96
Nandi	93
Baringo	67
Nakuru	26
Narok	89
Kajiado	27
Kericho	100
Bomet	69
Kakamega	103
Bungoma	92
Busia	86
Homa Bay	99
Migori	92
Kisii	69

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Discrete Map

This map shows the main % of mean forecast binned into discrete values. Averages are based on the most recent 10 year period of observed yields: 2006 - 2016

Analog Year Forecasts

Yield forecasts in analog years. <–DESCRIPTION OF ANALOG YEAR PROCESS–>.
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Analog Year Forecasts Errors

Forecast errors in analog years. If observed data is not available in a given year we cannot calculate forecast errors. Values are expressed a percentage of observed yields in a given year (t):

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\[\frac{(observed_{(t)}-forecast_{(t)})}{observed_{(t)}}\] ***

Positive (+) values indicate an under prediction. Negative (-) values indicate an over prediction.

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1. Extra/Extended Trees. A type of Random Forest Model↩︎