cassionData Analysis

Back to the lessonLesson 1 of 8The ladder is not the source

Four fifths improved, half with service

The same deck as the downloads, rendered as a page. Start the slideshow to present it full screen — arrow keys or a click advance one slide, Escape leaves.

Slides · PDFSlides · PowerPoint

  1. Slide 1 / 15

    What this lesson covers

    • The number most WASH reports give
    • The ladder the SDG indicator actually uses
    • Why the thirty minutes is in the definition
    • The rung this survey cannot compute
    • Report the distribution, not the top rung
    • What comes next
    Speaker notes
    82.3% of these households are on an improved source and 56.3% have at least basic drinking water service. The twenty-six points between the two are collection time, and they are the whole reason the ladder has rungs.

  2. Slide 2 / 15

    The number most WASH reports give — In Python

    import pandas as pd

households = pd.read_csv("wash-household-survey-2024.v1.csv")

IMPROVED = {                       # the JMP list, delivered water included
    "piped-into-dwelling", "piped-into-yard", "public-tap",
    "borehole", "protected-well", "protected-spring", "tanker-truck",
}
improved = households["water_source"].isin(IMPROVED)
print(f"improved source: {improved.mean():.1%} of {len(households)} households")
    Speaker notes
    Count the households on an improved source, divide by the households surveyed, and publish it as access.

  3. Slide 3 / 15

    The number most WASH reports give — In R

    library(dplyr)

improved <- c("piped-into-dwelling", "piped-into-yard", "public-tap",
              "borehole", "protected-well", "protected-spring",
              "tanker-truck")

households |> summarise(improved = mean(water_source %in% improved), n = n())

  4. Slide 4 / 15

    The number most WASH reports give

    • 82.3% — It is a correct calculation of a thing nobody asked about
    Speaker notes
    82.3%. It is a correct calculation of a thing nobody asked about.

  5. Slide 5 / 15

    The ladder the SDG indicator actually uses

    RungDefinition
    Safely managedAn improved source on premises, available when needed, and free from contamination
    BasicAn improved source, round trip 30 minutes or less including queueing
    LimitedAn improved source, round trip more than 30 minutes
    UnimprovedAn unprotected well or spring
    Surface waterRiver, dam, lake, pond, canal, irrigation channel
    Speaker notes
    The JMP drinking water ladder has four rungs, and the source type only decides which two you are choosing between.

  6. Slide 6 / 15

    The ladder the SDG indicator actually uses — In Python

    def ladder(row):
    if row["water_source"] == "surface-water":
        return "surface water"
    if row["water_source"] not in IMPROVED:
        return "unimproved"
    minutes = row["round_trip_minutes"]
    return "basic" if minutes <= 30 else "limited"

households["service"] = households.apply(ladder, axis=1)
print(households["service"].value_counts(normalize=True).round(3))
    Speaker notes
    SDG indicator 6.1.1 is the safely managed rung. The humanitarian reporting line, and the one most programmes are measured on, is at least basic — safely managed plus basic.

  7. Slide 7 / 15

    The ladder the SDG indicator actually uses — In R

    households |>
  mutate(service = case_when(
    water_source == "surface-water" ~ "surface water",
    !water_source %in% improved ~ "unimproved",
    round_trip_minutes <= 30 ~ "basic",
    TRUE ~ "limited"
  )) |>
  count(service) |>
  mutate(share = n / sum(n))

  8. Slide 8 / 15

    The ladder the SDG indicator actually uses

    RungHouseholdsShare
    Basic (including on premises)1,35256.3%
    Limited62626.1%
    Unimproved32613.6%
    Surface water994.1%

  9. Slide 9 / 15

    The ladder the SDG indicator actually uses

    • At least basic drinking water service: 56.3% — The source-type figure was 82.3%, and every one of the twenty-six points…
    Speaker notes
    At least basic drinking water service: 56.3%. The source-type figure was 82.3%, and every one of the twenty-six points between them is a household on an improved source it takes more than half an hour to reach and return from.

  10. Slide 10 / 15

    Why the thirty minutes is in the definition

    • households collect less water, so quantity falls below the Sphere minimum more often;
    • collection is done by women and girls, so the time comes out of school attendance and paid work;
    • households supplement from a nearer, worse source, so the recorded source is not the only source.
    • A definition that looks bureaucratic usually encodes a finding — Before arguing that a threshold is arbitrary, look for…
    Speaker notes
    It is not administrative tidiness. A round trip over thirty minutes changes behaviour in ways that are measurable elsewhere in this same file: A definition that looks bureaucratic usually encodes a finding. Before arguing that a threshold is arbitrary, look for the thing it was set to separate.

  11. Slide 11 / 15

    The rung this survey cannot compute — In Python

    on_premises = (households["round_trip_minutes"] == 0)
tested = households["ecoli_cfu_100ml"].notna()

print(f"on premises: {on_premises.mean():.1%}")
print(f"water quality tested: {tested.mean():.1%}")
print(f"both: {(on_premises & tested).mean():.1%}")
    Speaker notes
    Safely managed needs three conditions and this file supports one of them.

  12. Slide 12 / 15

    The rung this survey cannot compute — In R

    households |> summarise(
  on_premises = mean(round_trip_minutes == 0),
  tested = mean(!is.na(ecoli_cfu_100ml))
)
    Speaker notes
    27.7% of households have water on premises. Availability when needed is not asked. Freedom from contamination is tested on a third of the sample. So safely managed is not computable here, and the honest report says so rather than reporting on-premises as though it were the top rung. That is the commonest way an SDG figure gets overstated: one of three conditions is measured, and the indicator is published under the name of all three.

  13. Slide 13 / 15

    Report the distribution, not the top rung — Example

    Drinking water service level, 2,403 households

  At least basic         56.3%   1,352
    of which on premises 27.7%     665
  Limited                26.1%     626
  Unimproved             13.6%     326
  Surface water           4.1%      99

  JMP ladder. Safely managed not computable: availability was not asked and
  water quality was tested on 33.4% of households.
    Speaker notes
    Every rung, with counts. A report that gives only "56.3% have basic service" hides that a quarter of the population is one threshold away and would move with a nearer water point — which is exactly the group a programme can act on.

  14. Slide 14 / 15

    What comes next

    • Water has one ladder and two more are waiting.
    Speaker notes
    Water has one ladder and two more are waiting. The next lesson does sanitation and hygiene, where the equivalent of the thirty-minute rule is a single boolean column that quietly halves a coverage figure.

  15. Slide 15 / 15

    Where this goes next

    Read the full lesson, with runnable code Back to the lesson