Scalars and multipliers¶
The following parameters scale or multiply values set in other areas of the configuration file or other input files. This can be especially useful for understanding the sensitivities of disease dynamics to input data without requiring modifications to those base values. For example, one might set x_Birth to a value less than 1 to simulate a lower future birth rate due to increased economic prosperity and available medical technology.
Note
Parameters are casesensitive. For Boolean parameters, set to 1 for true or 0 for false. Minimum, maximum, or default values of “NA” indicate that those values are not applicable for that parameter.
EMOD does not use true defaults; that is, if the dependency relationships indicate that a parameter is required, you must supply a value for it. However, many of the tools used to work with EMOD will use the default values provided below.
JSON format does not permit comments, but you can add “dummy” parameters to add contextual information to your files. Any keys that are not EMOD parameter names will be ignored by the model.
Parameter 
Data type 
Minimum 
Maximum 
Default 
Description 
Example 

Acquire_Modifier 
float 
0 
1 
1 
Modifier of the probability of successful infection of a mosquito by an infected individual, given the individual’s infectiousness. 
{
"Vector_Species_Params": [
{
"Acquire_Modifier": 1,
"Name": "arabiensis"
}
]
}

Antibody_IRBC_Kill_Rate 
double 
NA 
NA 
2 
The scale factor multiplied by antibody level to produce the rate of clearance of the infected red blood cell (IRBC) population. 
{
"Antibody_IRBC_Kill_Rate": 1.595
}

Aquatic_Arrhenius_1 
float 
0 
1.00E+15 
8.42E+10 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the daily rate of fractional progression of mosquito aquatic development (egghatching through emergence). This duration is a decreasing function of temperature. The variable a1 is a temperatureindependent scale factor on development rate. 
{
"Vector_Species_Params": [
{
"Aquatic_Arrhenius_1": 9752291.727,
"Name": "arabiensis"
}
]
}

Aquatic_Arrhenius_2 
float 
0 
1.00E+15 
8328 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the daily rate of fractional progression of mosquito aquatic development (egghatching through emergence). This duration is a decreasing function of temperature. The variable a2 governs how quickly the rate changes with temperature. 
{
"Vector_Species_Params": [
{
"Aquatic_Arrhenius_2": 8328,
"Name": "arabiensis"
}
]
}

Birth_Rate_Time_Dependence 
enum 
NA 
NA 
NONE 
A scale factor for BirthRate that allows it to be altered by time or season. Enable_Birth must be set to true (1). Possible values are:

{
"Enable_Vital_Dynamics": 1,
"Enable_Birth": 1,
"Birth_Rate_Time_Dependence": "ANNUAL_BOXCAR_FUNCTION"
}

Cycle_Arrhenius_1 
float 
0 
1.00E+15 
4.09E+10 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the mosquito feeding cycle rate. This duration is a decreasing function of temperature. The variable a1 is a temperatureindependent scale factor on feeding rate. Temperature_Dependent_Feeding_Cycle must be set to ARRHENIUS_DEPENDENCE. 
{
"Vector_Species_Params": [
{
"Cycle_Arrhenius_1": 99,
"Cycle_Arrhenius_2": 88,
"Name": "arabiensis",
"Temperature_Dependent_Feeding_Cycle": "ARRHENIUS_DEPENDENCE"
}
]
}

Cycle_Arrhenius_2 
float 
0 
1.00E+15 
7740 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the mosquito feeding cycle rate. This duration is a decreasing function of temperature. The variable a2 is a temperatureindependent scale factor on feeding rate. Temperature_Dependent_Feeding_Cycle must be set to ARRHENIUS_DEPENDENCE. 
{
"Vector_Species_Params": [
{
"Cycle_Arrhenius_1": 99,
"Cycle_Arrhenius_2": 88,
"Name": "arabiensis",
"Temperature_Dependent_Feeding_Cycle": "ARRHENIUS_DEPENDENCE"
}
]
}

Cycle_Arrhenius_Reduction_Factor 
float 
0 
1 
1 
The scale factor applied to cycle duration (from oviposition to oviposition) to reduce the duration when primary follicles are at stage II rather than I in the case of newly emerged females. Temperature_Dependent_Feeding_Cycle must be set to ARRHENIUS_DEPENDENCE. 
{
"Vector_Species_Params": [
{
"Cycle_Arrhenius_Reduction_Factor": 0.44,
"Name": "arabiensis",
"Temperature_Dependent_Feeding_Cycle": "ARRHENIUS_DEPENDENCE"
}
]
}

Egg_Arrhenius1 
float 
0 
1.00E+10 
6.16E+07 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the daily rate of mosquito egg hatching. This duration is a decreasing function of temperature. The variable a1 is a temperatureindependent scale factor on hatching rate. Enable_Temperature_Dependent_Egg_Hatching must be set to 1. 
{
"Enable_Temperature_Dependent_Egg_Hatching": 1,
"Egg_Arrhenius1": 61599956,
"Egg_Arrhenius2": 5754
}

Egg_Arrhenius2 
float 
0 
1.00E+10 
5754.03 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the daily rate of mosquito egg hatching. This duration is a decreasing function of temperature. The variable a2 is a temperaturedependent scale factor on hatching rate. Enable_Temperature_Dependent_Egg_Hatching must be set to 1. 
{
"Enable_Temperature_Dependent_Egg_Hatching": 1,
"Egg_Arrhenius1": 61599956,
"Egg_Arrhenius2": 5754
}

Infected_Arrhenius_1 
float 
0 
1.00E+15 
1.17E+11 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the daily rate of fractional progression of infected mosquitoes to an infectious state. The duration of sporogony is a decreasing function of temperature. The variable a1 is a temperatureindependent scale factor on the progression rate to infectiousness. 
{
"Vector_Species_Params": [
{
"Name": "arabiensis",
"Acquire_Modifier": 0.2,
"Adult_Life_Expectancy": 20,
"Anthropophily": 0.65,
"Aquatic_Arrhenius_1": 84200000000,
"Aquatic_Arrhenius_2": 8328,
"Aquatic_Mortality_Rate": 0.1,
"Days_Between_Feeds": 3,
"Egg_Batch_Size": 100,
"Habitats": [
{
"Habitat_Type": "TEMPORARY_RAINFALL",
"Max_Larval_Capacity": 11250000000
}
],
"Immature_Duration": 2,
"Indoor_Feeding_Fraction": 1,
"Infected_Arrhenius_1": 117000000000,
"Infected_Arrhenius_2": 8336,
"Infected_Egg_Batch_Factor": 0.8,
"Infectious_Human_Feed_Mortality_Factor": 1.5,
"Male_Life_Expectancy": 10,
"Temperature_Dependent_Feeding_Cycle": "NO_TEMPERATURE_DEPENDENCE",
"Transmission_Rate": 0.5,
"Vector_Sugar_Feeding_Frequency": "VECTOR_SUGAR_FEEDING_NONE"
}
]
}

Infected_Arrhenius_2 
float 
0 
1.00E+15 
8340 
The Arrhenius equation, \(a_1^{a_2/T}\), with T in degrees Kelvin, parameterizes the daily rate of fractional progression of infected mosquitoes to an infectious state. The duration of sporogony is a decreasing function of temperature. The variable a2 is a temperaturedependent scale factor on the progression rate to infectiousness. 
{
"Vector_Species_Params": [
{
"Name": "arabiensis",
"Acquire_Modifier": 0.2,
"Adult_Life_Expectancy": 20,
"Anthropophily": 0.65,
"Aquatic_Arrhenius_1": 84200000000,
"Aquatic_Arrhenius_2": 8328,
"Aquatic_Mortality_Rate": 0.1,
"Days_Between_Feeds": 3,
"Egg_Batch_Size": 100,
"Habitats": [
{
"Habitat_Type": "TEMPORARY_RAINFALL",
"Max_Larval_Capacity": 11250000000
}
],
"Immature_Duration": 2,
"Indoor_Feeding_Fraction": 1,
"Infected_Arrhenius_1": 117000000000,
"Infected_Arrhenius_2": 8336,
"Infected_Egg_Batch_Factor": 0.8,
"Infectious_Human_Feed_Mortality_Factor": 1.5,
"Male_Life_Expectancy": 10,
"Temperature_Dependent_Feeding_Cycle": "NO_TEMPERATURE_DEPENDENCE",
"Transmission_Rate": 0.5,
"Vector_Sugar_Feeding_Frequency": "VECTOR_SUGAR_FEEDING_NONE"
}
]
}

Infected_Egg_Batch_Factor 
float 
0 
10 
0.8 
The dimensionless factor used to modify mosquito egg batch size in order to account for reduced fertility effects arising due to infection (e.g. when females undergo sporogony). 
{
"Vector_Species_Params": [
{
"Name": "arabiensis",
"Acquire_Modifier": 0.2,
"Adult_Life_Expectancy": 20,
"Anthropophily": 0.65,
"Aquatic_Arrhenius_1": 84200000000,
"Aquatic_Arrhenius_2": 8328,
"Aquatic_Mortality_Rate": 0.1,
"Days_Between_Feeds": 3,
"Egg_Batch_Size": 100,
"Habitats": [
{
"Habitat_Type": "TEMPORARY_RAINFALL",
"Max_Larval_Capacity": 11250000000
}
],
"Immature_Duration": 2,
"Indoor_Feeding_Fraction": 1,
"Infected_Arrhenius_1": 117000000000,
"Infected_Arrhenius_2": 8336,
"Infected_Egg_Batch_Factor": 0.8,
"Infectious_Human_Feed_Mortality_Factor": 1.5,
"Male_Life_Expectancy": 10,
"Temperature_Dependent_Feeding_Cycle": "NO_TEMPERATURE_DEPENDENCE",
"Transmission_Rate": 0.5,
"Vector_Sugar_Feeding_Frequency": "VECTOR_SUGAR_FEEDING_NONE"
}
]
}

Infectious_Human_Feed_Mortality_Factor 
float 
0 
1000 
1.5 
The (dimensionless) factor used to modify the death rate of mosquitoes when feeding on humans, to account for the higher mortality rate infected mosquitoes experience during human feeds versus uninfected mosquitoes. 
{
"Vector_Species_Params": [
{
"Name": "arabiensis",
"Acquire_Modifier": 0.2,
"Adult_Life_Expectancy": 20,
"Anthropophily": 0.65,
"Aquatic_Arrhenius_1": 84200000000,
"Aquatic_Arrhenius_2": 8328,
"Aquatic_Mortality_Rate": 0.1,
"Days_Between_Feeds": 3,
"Egg_Batch_Size": 100,
"Habitats": [
{
"Habitat_Type": "TEMPORARY_RAINFALL",
"Max_Larval_Capacity": 11250000000
}
],
"Immature_Duration": 2,
"Indoor_Feeding_Fraction": 1,
"Infected_Arrhenius_1": 117000000000,
"Infected_Arrhenius_2": 8336,
"Infected_Egg_Batch_Factor": 0.8,
"Infectious_Human_Feed_Mortality_Factor": 1.5,
"Male_Life_Expectancy": 10,
"Temperature_Dependent_Feeding_Cycle": "NO_TEMPERATURE_DEPENDENCE",
"Transmission_Rate": 0.5,
"Vector_Sugar_Feeding_Frequency": "VECTOR_SUGAR_FEEDING_NONE"
}
]
}

Infectivity_Exponential_Baseline 
float 
0 
1 
0 
The scale factor applied to Base_Infectivity at the beginning of a simulation, before the infectivity begins to grow exponentially. Infectivity_Scale_Type must be set to EXPONENTIAL_FUNCTION_OF_TIME. 
{
"Infectivity_Exponential_Baseline": 0.1,
"Infectivity_Exponential_Delay": 90,
"Infectivity_Exponential_Rate": 45,
"Infectivity_Scale_Type": "EXPONENTIAL_FUNCTION_OF_TIME"
}

Larval_Density_Mortality_Scalar 
float 
0.01 
1000 
10 
A scale factor in the formula determining the larvalagedependent mortality for the GRADUAL_INSTAR_SPECIFIC and LARVAL_AGE_DENSITY_DEPENDENT_MORTALITY_ONLY models. 
{
"Larval_Density_Mortality_Scalar": 1.0
}

Newborn_Biting_Risk_Multiplier 
float 
0 
1 
0.2 
The scale factor that defines the yintercept of the linear portion of the biting risk curve when Age_Dependent_Biting_Risk_Type is set to LINEAR. 
{
"Newborn_Biting_Risk_Multiplier": 0.2
}

Nonspecific_Antibody_Growth_Rate_Factor 
float 
0 
1000 
0.5 
The factor that adjusts Antibody_Capacity_Growth_Rate for less immunogenic surface proteins, called minor epitopes. 
{
"Nonspecific_Antibody_Growth_Rate_Factor": 0.5
}

Population_Scale_Type 
enum 
NA 
NA 
USE_INPUT_FILE 
The method to use for scaling the initial population specified in the demographics input file. Possible values are:

{
"Population_Scale_Type": "FIXED_SCALING"
}

Post_Infection_Acquisition_Multiplier 
float 
0 
1 
0 
The multiplicative reduction in the probability of reacquiring disease. At the time of recovery, the immunity against acquisition is multiplied by Acquisition_Blocking_Immunity_Decay_Rate x (1  Post_Infection_Acquisition_Multiplier). Enable_Immunity must be set to 1 (true). 
{
"Enable_Immunity": 1,
"Enable_Immune_Decay": 1,
"Post_Infection_Acquisition_Multiplier": 0.9
}

Post_Infection_Mortality_Multiplier 
float 
0 
1 
0 
The multiplicative reduction in the probability of dying from infection after getting reinfected. At the time of recovery, the immunity against mortality is multiplied by Mortality_Blocking_Immunity_Decay_Rate x (1  Post_Infection_Mortality_Multiplier). Enable_Immunity must be set to 1 (true). 
{
"Enable_Immunity": 1,
"Enable_Immune_Decay": 1,
"Post_Infection_Mortality_Multiplier": 0.5
}

Post_Infection_Transmission_Multiplier 
float 
0 
1 
0 
The multiplicative reduction in the probability of transmitting infection after getting reinfected. At the time of recovery, the immunity against transmission is multiplied by Transmission_Blocking_Immunity_Decay_Rate x (1  Post_Infection_Transmission_Multiplier). Enable_Immunity must be set to 1 (true). 
{
"Enable_Immunity": 1,
"Enable_Immunity_Decay": 1,
"Post_Infection_Transmission_Multiplier": 0.9
}

Vector_Migration_Food_Modifier 
float 
0 
3.40E+38 
0 
The preference of a vector to migrate toward a node currently occupied by humans, independent of the number of humans in the node. Used only when Vector_Sampling_Type is set to TRACK_ALL_VECTORS. Enable_Vector_Migration must be set to 1. 
{
"Vector_Migration_Food_Modifier": 1.0
}

Vector_Migration_Habitat_Modifier 
float 
0 
3.40E+38 
0 
The preference of a vector to migrate toward a node with more habitat. Only used when Vector_Sampling_Type is set to TRACK_ALL_VECTORS. Enable_Vector_Migration must be set to 1. 
{
"Vector_Migration_Habitat_Modifier": 1.0
}

Vector_Migration_Modifier_Equation 
enum 
NA 
NA 
LINEAR 
The functional form of vector migration modifiers. Enable_Vector_Migration must be set to 1. Possible values are: LINEAR EXPONENTIAL 
{
"Vector_Migration_Modifier_Equation": "EXPONENTIAL"
}

Vector_Migration_Stay_Put_Modifier 
float 
0 
3.40E+38 
0 
The preference of a vector to remain in its current node rather than migrate to another node. Used only when Vector_Sampling_Type is set to TRACK_ALL_VECTORS. Enable_Vector_Migration must be set to 1. 
{
"Vector_Migration_Stay_Put_Modifier": 1.0
}

x_Air_Migration 
float 
0 
3.40E+38 
1 
Scale factor for the rate of migration by air, as provided by the migration file. Enable_Air_Migration must be set to 1. 
{
"Scale_Factor_Air_Migration": 1
}

x_Base_Population 
float 
0 
3.40E+38 
1 
Scale factor for InitialPopulation in the demographics file (see NodeAttributes parameters). If Population_Scale_Type is set to FIXED_SCALING, the initial simulation population is uniformly scaled over the entire area to adjust for historical or future population density. 
{
"x_Base_Population": 0.0001
}

x_Birth 
float 
0 
3.40E+38 
1 
Scale factor for birth rate, as provided by the demographics file (see NodeAttributes parameters). Enable_Birth must be set to 1. 
{
"x_Birth": 1
}

x_Family_Migration 
float 
0 
3.40E+38 
1 
Scale factor for the rate of migration by families, as provided by the migration file. Enable_Family_Migration must be set to true (1). 
{
"x_Family_Migration": 1
}

x_Local_Migration 
float 
0 
3.40E+38 
1 
Scale factor for rate of migration by foot travel, as provided by the migration file. Enable_Local_Migration must be set to 1. 
{
"x_Local_Migration": 1
}

x_Other_Mortality 
float 
0 
3.40E+38 
1 
Scale factor for mortality from causes other than the disease being simulated. Base mortality is provided by the demographics file (see Complex distributions parameters). Enable_Natural_Mortality must be set to 1. 
{
"x_Other_Mortality": 1
}

x_Regional_Migration 
float 
0 
3.40E+38 
1 
Scale factor for the rate of migration by road vehicle, as provided by the migration file. Enable_Regional_Migration must be set to 1. 
{
"x_Regional_Migration": 1
}

x_Sea_Migration 
float 
0 
3.40E+38 
1 
Scale factor for the rate of migration by sea, as provided by the migration file. Enable_Sea_Migration must be set to 1. 
{
"x_Sea_Migration": 1
}

x_Temporary_Larval_Habitat 
float 
0 
10000 
1 
Scale factor for the habitat size for all mosquito populations. 
{
"x_Temporary_Larval_Habitat": 1
}

x_Vector_Migration_Local 
float 
0 
3.40E+38 
1 
Scale factor for the rate of vector migration to adjacent nodes, as provided by the vector migration file. Enable_Vector_Migration must be set to 1. 
{
"x_Vector_Migration_Local": 1.0
}

x_Vector_Migration_Regional 
float 
0 
3.40E+38 
1 
Scale factor for the rate of vector migration to nonadjacent nodes, as provided by the vector migration file. Enable_Vector_Migration must be set to 1. 
{
"x_Vector_Migration_Regional": 1.0
}
