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--- lesson_18 [2020/02/11 13:23]
argemiro
+++ lesson_18 [2020/02/13 06:59]
britaldo
@@ Line 14: / Line 14: @@
 * Functors: \\ - //[[:Determine Weights Of Evidence Ranges]]//\\ - //[[:Determine Weights Of Evidence Coefficients]]//\\ - //[[:calc_w._of_e._probability_map|Calc W. Of E. Probability Map]]//\\ - //[[:Calc Change Matrix]]//\\ - //[[:Patcher]]//\\ - //[[:Expander]]//\\
-This lesson explores the use of Dinamica EGO as a simulation platform for land-use and cover change (LUCC) models. The goal is to calibrate, run and validate a LUCC model, in this case a simulation model of deforestation. You will need to go through 10 steps in order to complete the model, as depicted in the fig.1 . To facilitate this process, each one of these steps will be represented as a separate model. Although, all steps could be joined into a single model, for reason of simplicity we will keep them as separate models.
+This lesson explores the use of Dinamica EGO as a simulation platform for land-use and cover change (LUCC) models. The goal is to calibrate, run and validate a LUCC model, in this case a simulation model of deforestation. You will need to go through 10 steps in order to complete the model, as depicted in the fig.1 . To facilitate this process, each one of these steps will be represented as a separate model. Although, all steps could be joined into a single model, for sake of simplicity we will keep them as separate models.
 {{ :steps_lucc_model.png?900 |}}
@@ Line 37: / Line 37: @@
-<note tip>**TIP**: Keep in mind the numbers that identify the map classes, since Dinamica EGO does not explicitly handle class names.</note>
+<note tip>**TIP**: Keep in mind the numbers that identify the map classes, since Dinamica EGO does not explicitly handle class names, although they can be visualized in the viewer with customized colors and specified in the metadata as well as in the header of geotiff files. See functor Assign Map Categories.</note>
 ==== First step: Calculating transition matrices ====
-First, you need to calculate the historical transition matrices. The transition matrix describes a system that changes over discrete time increments, in which the value of any variable in a given time period is the sum of fixed percentages of values of all variables in the previous time step. The sum of fractions along the column of the transition matrix is equal to one. The diagonal line of the transition matrix does not need to be specified since Dinamica EGO does not model the percentage of unchangeable cells, nor do the transitions equal to zero. The transition rate can be passed to the LUCC model as a fixed parameter or be updated from model feedback.
+First, you need to calculate the historical transition matrices. The transition matrix describes a system that changes over discrete time increments, in which the value of any variable in a given time period is the sum of fixed percentages of values of all variables in the previous time step. The sum of fractions along the column of the transition matrix is equal to one. The diagonal line of the transition matrix does not need to be specified since Dinamica EGO does not model the percentage of unchangeable cells, nor the transitions equal to zero. The transition rate can be passed to the LUCC model as a fixed parameter or be updated from model feedback.
 {{:tutorial:lucc_3.jpg?300|}}(1)
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 The single-step matrix corresponds to a time period represented as a single time step, in turn the multiple-step matrix corresponds to a time step unit (year, month, day, etc) specified by dividing the time period by a number of time steps. For Dinamica EGO, time step can comprise any span of time, since time unit is only an external reference. A multiple-step transition matrix can only be derived from an Ergodic matrix, i.e. a matrix that has real number Eigen values and vectors.
-The transition rates set the net quantity of changes, that is, the percentage of land that will change to another state (land use and cover attribute), and thus they are known as net rates, being adimensional. In turn, gross rates are specified as an area unit, such as hectares or km<sup>2</sup> per unit of time. In the case that there is not a solution for the multiple-step transition matrix, you still can run the model in several time steps, as defined above, calculating a fixed gross rate per time step (e.g. year) by dividing the accumulated change over the period by the number of steps over which the period is composed (this might not apply to complex transition model). Dinamica EGO converts gross rates into net rate, dividing the extent of change by the fraction of each land use and cover class prior to change, before passing it to the transition functors: //[[:Patcher]]// and //[[:Expander]]//.\\
+The transition rates set the net quantity of changes, that is, the percentage of land that will change to another state (land use and cover attribute), and thus they are known as net rates, and denoted in percentage. In turn, gross rates are specified as an area unit, such as hectares or km<sup>2</sup> per unit of time. In the case that there is not a solution for the multiple-step transition matrix, you still can run the model in several time steps, as defined above, calculating a fixed gross rate per time step (e.g. year) by dividing the accumulated change over the period by the number of steps over which the period is composed (this might not apply to complex transition model). Dinamica EGO converts gross rates into net rate, dividing the extent of change by the fraction of each land use and cover class prior to change, before passing it to the transition functors: //[[:Patcher]]// and //[[:Expander]]//.\\
 Open the model ''determine_transition_matrix.egoml'' located in ''\Guidebook_Dinamica_5\Models\LUCC_model\1_transition_matrix_calculation''\\