cts:triple-range-query should consider reference value in score calculation

Question

I have the following cts:triple-range-query:

let $frequency_query := cts:properties-fragment-query(
  cts:triple-range-query(
    sem:iri("http://star-group.net/skc/0.1/07-30"),
    sem:iri("http://star-group.net/skc/0.1/hasFrequency"),
    0.0,
    ">=",
    ("score-function=linear","slope-factor=1024.0"),
    1
  )
)

I want to include it as a range query in the score calculation, according to Including a Range or Geospatial Query in Scoring. Somehow I can't configure the slope-factor suche that it works with the interval [0,1]. I want to score values that are closer to 1 with a higher score.

My response includes 45 entries. The top 3 have a (relative) frequency bigger than 0.0 and the others have all 0.0.

1. 0.2289156626506024
2. 0.3325301204819277
3. 0.41445783132530123
4. 0

...

45. 0

However, the first 3 results have all a score of 16384. I expect the first 3 results to have 3 different scores (descending according the the relative frequency).

Complete Query:

xquery version "1.0-ml";

let $language as xs:string := "lang:en"
let $variant as xs:string := "model_x"

let $search_option := ("score-logtf", "relevance-trace")


let $frequency_query := cts:properties-fragment-query(
  cts:triple-range-query(
    sem:iri("http://star-group.net/skc/0.1/07-30"),
    sem:iri("http://star-group.net/skc/0.1/hasFrequency"),
    0.0,
    ">=",
    ("score-function=linear","slope-factor=1024.0"),
    1
  )
)

let $query := cts:and-query((
  cts:element-attribute-word-query(
    xs:QName("MATERIAL"),
    xs:QName("ANKER"), $variant,
    (),
    0
  ),
  cts:collection-query("project:Y"),
  cts:collection-query($language),
  cts:boost-query(
    cts:collection-query("doctype:MATERIAL"),
    $frequency_query
  )
)
return cts:search(/, $query, $search_option, 0)