Create a one-level two-arm design — two_arm

Builds a design with one treatment and one control arm. Treatment effects can be specified either by providing control_mean and treatment_mean or by specifying a control_mean and ate.

two_arm_designer(
  N = 100,
  assignment_prob = 0.5,
  control_mean = 0,
  control_sd = 1,
  ate = 1,
  treatment_mean = control_mean + ate,
  treatment_sd = control_sd,
  rho = 1,
  args_to_fix = NULL
)

Arguments

N: An integer. Sample size.
assignment_prob: A number in [0,1]. Probability of assignment to treatment.
control_mean: A number. Average outcome in control.
control_sd: A positive number. Standard deviation in control.
ate: A number. Average treatment effect.
treatment_mean: A number. Average outcome in treatment. Overrides ate if both specified.
treatment_sd: A nonnegative number. Standard deviation in treatment. By default equals control_sd.
rho: A number in [-1,1]. Correlation between treatment and control outcomes.
args_to_fix: A character vector. Names of arguments to be args_to_fix in design.

Value

A simple two-arm design.

Details

Units are assigned to treatment using complete random assignment. Potential outcomes are normally distributed according to the mean and sd arguments.

Author

DeclareDesign Team

Examples

# Generate a simple two-arm design using default arguments
two_arm_design <- two_arm_designer()