Reference Data Standard Protocols

Kamini YadavDr. Russ Congalton

Current Process Flow Chart

Testing Protocol on Mali data

• Evaluate Mali data collected in August 2015 by Murali, according to the flowchart made by Justin

Large Scale, LS (>20ha) Medium Scale, MS(10-20 ha) Small Scale, SS(<10ha) Very Large Scale, VLS Very Very Large Scale, VVLS

Field collected Created by Justin

Mali Ground Data (August 2015, Murali)

Need to know/understand……

• How to handle multiple crops in single sample?

• What does scale mean here? • How does this scale help in deciding

homogeneous samples at 250m/90m sample unit?

• What the date of the collection of crop data?

Steps to crosswalk the Mali data into our standard protocol format

• Extract the single crop samples because they conform to the homogeneity requirement due to the presence of a single crop

• Check the homogeneity of each sampling unit in a 250mX 250m window on Google Earth (using high resolution imagery)

Checking Mali data using Google Earth

• The images of some samples do not look like a single crop

• Some samples might not have crops before the growing season (left as fallow)

• Are the coordinates correct (are we in the right place)?

Issue: Proximity to Road

2014

• Need to implement some automated filter on the entire dataset based on some minimum distance to the road layer

• All the samples near to road (within certain distance) must be flagged for evaluation or moved to the center of a field

April 2014

November 2013

Issue - continued

Issue - continued

February 2014

VVLS?? – very, very large scaleDoes this mean only homogeneous crops are there so that we can move the sample inside the field and away from the road?

2014

February 2015

VLS -Very Large scale??We need to understand this scale term so that we can determine how far the samples can be moved away from the road and into the field and yet remain a homogeneous sample unit.

Issue - continued

March2013

• Includes settlement in the yellow window.

• This is Large scale (LS) but does not look homogeneous???

Issue - Close to settlement

February 2011

June 2013Include settlements in the yellow window

Question - So close to settlements may be indication of the wrong

geographic coordinates???

September 2013

January 2014

The sample includes a waterbody in 250m by 250m homogeneous

window?

December 2013

Not homogeneous

Close to the coastline

Photograph taken of the sample unit does not look

like Maize crop as mentioned in description

February 2014

December2011

February 2014

Homogeneity vs. Scale

Large scale??In Google Earth, the 250x250m window does not look homogeneous; Photograph seems to be of more than one crops

VLS…does this scene indicate homogeneity for one crop type??

Issue - homogeneity

Important Issues to be solved

• Identify the single crop sample units• Decide homogeneous samples from different

scale levels – very confusing• Perform stratification and identify samples for

each class label• In addition to minimum distance between

samples (spatial autocorrelation), use minimum distance to roads, settlements, and waterbodies. This analysis must be added to the flow chart.

Thank you

Questions?