diff --git a/src/benchmark/benchmark_result.rs b/src/benchmark/benchmark_result.rs
index 27ff543..1012d31 100644
--- a/src/benchmark/benchmark_result.rs
+++ b/src/benchmark/benchmark_result.rs
@@ -14,15 +14,6 @@ pub struct Parameter {
 
 /// Meta data and performance metrics for a single benchmark
 #[derive(Debug, Default, Clone, Serialize, PartialEq)]
-#[serde(transparent)]
-pub struct Parameter {
-    pub value: String,
-    #[serde(skip)]
-    pub is_unused: bool,
-}
-
-/// Meta data and performance metrics for a single benchmark
-#[derive(Debug, Default, Clone, PartialEq)]
 pub struct BenchmarkResult {
     /// The full command line of the program that is being benchmarked
     pub command: String,
diff --git a/src/benchmark/mod.rs b/src/benchmark/mod.rs
index d4d3f3e..c473f9b 100644
--- a/src/benchmark/mod.rs
+++ b/src/benchmark/mod.rs
@@ -259,7 +259,8 @@ impl<'a> Benchmark<'a> {
             None
         };
 
-        let preparation_result = run_preparation_command()?;
+        let benchmark_iteration = BenchmarkIteration::Benchmark(0);
+        let preparation_result = run_preparation_command(benchmark_iteration)?;
         let preparation_overhead = preparation_result.map_or(Time::zero(), |res| {
             res.time_wall_clock + self.executor.time_overhead()
         });
@@ -288,7 +289,7 @@ impl<'a> Benchmark<'a> {
             );
         }
 
-        let conclusion_result = run_conclusion_command()?;
+        let conclusion_result = run_conclusion_command(benchmark_iteration)?;
         let conclusion_overhead = conclusion_result.map_or(Time::zero(), |res| {
             res.time_wall_clock + self.executor.time_overhead()
         });
diff --git a/src/quantity/statistics.rs b/src/quantity/statistics.rs
index ffc9612..9434b41 100644
--- a/src/quantity/statistics.rs
+++ b/src/quantity/statistics.rs
@@ -107,7 +107,7 @@ pub fn standard_deviation<Q: UnsafeRawValue>(values: impl IntoIterator<Item = Q>
     Q::unsafe_from_raw_value(result)
 }
 
-/// Compute modifized Z-scores for a given sample. A (unmodified) Z-score is defined by
+/// Compute modified Z-scores for a given sample. A (unmodified) Z-score is defined by
 /// `(x_i - x_mean)/x_stddev` whereas the modified Z-score is defined by `(x_i - x_median)/MAD`
 /// where MAD is the median absolute deviation.
 ///