Update README.md

README.md

@@ -35,8 +35,8 @@ Participants receive collections of short audio fragments (~3 seconds each) extr
 **The task is to estimate the number of individuals of the target species in each aviary.**
 
 For full task details, timeline, evaluation criteria, and submission instructions, see:
-- **Task website:** [https://www.ml4biodiversity.org/biodcase26_birdcounts/](https://www.ml4biodiversity.org/biodcase26_birdcounts/)
-- **Task (Challenge) page:** [https://biodcase.github.io/challenge2026/](https://biodcase.github.io/challenge2026/)
+- **Task page:** [https://www.ml4biodiversity.org/biodcase26_birdcounts/](https://www.ml4biodiversity.org/biodcase26_birdcounts/)
+- **Challenge page:** [https://biodcase.github.io/challenge2026/](https://biodcase.github.io/challenge2026/)
 - **Baseline code:** [https://github.com/ml4biodiversity/biodcase-population-estimation](https://github.com/ml4biodiversity/biodcase-population-estimation)
 
 ## Dataset description
@@ -49,9 +49,9 @@ Three bird species are designated as estimation targets. Population estimation i
 
 | Species | Scientific name | Aviaries | Population range |
 |---|---|---|---|
-| Greater flamingo | *Phoenicopterus roseus* | aviary_2, aviary_4, aviary_5, aviary_6 | 52–161 |
-| Red-billed quelea | *Quelea quelea* | aviary_1, aviary_3 | 61–153 |
-| Hadada ibis | *Bostrychia hagedash* | aviary_2, aviary_4 | 4–6 |
+| Greater flamingo | *Phoenicopterus roseus* | dev_aviary_2, dev_aviary_4, dev_aviary_5, dev_aviary_6 | 52–161 |
+| Red-billed quelea | *Quelea quelea* | dev_aviary_1, dev_aviary_3 | 61–153 |
+| Hadada ibis | *Bostrychia hagedash* | dev_aviary_2, dev_aviary_4 | 4–6 |
 
 Each aviary also contains additional non-target bird species (2–12 species per aviary, 28 species in total across all aviaries). The complete species inventory with population counts is provided in `metadata/ground_truth.csv`.
 
@@ -59,25 +59,25 @@ Each aviary also contains additional non-target bird species (2–12 species per
 
 | Aviary | Days | Audio files | Target species | Target population |
 |---|---|---|---|---|
-| aviary_1 | 3 | 12,627 | Red-billed quelea | 153 |
-| aviary_2 | 3 | 25,569 | Greater flamingo (107), Hadada ibis (6) | 113 |
-| aviary_3 | 3 | 11,879 | Red-billed quelea | 61 |
-| aviary_4 | 3 | 36,340 | Greater flamingo (161), Hadada ibis (4) | 165 |
-| aviary_5 | 2 | 19,363 | Greater flamingo | 52 |
-| aviary_6 | 3 | 35,121 | Greater flamingo | 52 |
+| dev_aviary_1 | 3 | 12,627 | Red-billed quelea | 153 |
+| dev_aviary_2 | 3 | 25,569 | Greater flamingo (107), Hadada ibis (6) | 113 |
+| dev_aviary_3 | 3 | 11,879 | Red-billed quelea | 61 |
+| dev_aviary_4 | 3 | 36,340 | Greater flamingo (161), Hadada ibis (4) | 165 |
+| dev_aviary_5 | 2 | 19,363 | Greater flamingo | 52 |
+| dev_aviary_6 | 3 | 35,121 | Greater flamingo | 52 |
 | **Total** | **17** | **140,899** | | |
 
 **Note:** Aviary 5 and aviary 6 are two separate recording sessions from the same physical location with the same bird population, captured on different dates. They are treated as independent data points with different acoustic conditions.
 
 ### Audio format
 
-All audio files are WAV files, 16-bit PCM, sampled at **48 kHz**, with a duration of approximately **3 seconds** each. The files represent consecutive, non-overlapping segments extracted from continuous recordings.
+All audio files are single-channel (mono) WAV files, 16-bit PCM, sampled at **48 kHz**, with a duration of approximately **3 seconds** each. The files represent consecutive, non-overlapping segments extracted from continuous recordings.
 
 ## Dataset structure
 
 ```
 BioDCASE2026_Bird_Counting/
-├── aviary_1/
+├── dev_aviary_1/
 │   ├── chunk_000/
 │   │   ├── rec_d1_00_00_45.750000.wav
 │   │   ├── rec_d1_00_01_49.wav
@@ -85,15 +85,15 @@ BioDCASE2026_Bird_Counting/
 │   ├── chunk_001/
 │   │   └── ...
 │   └── ...
-├── aviary_2/
+├── dev_aviary_2/
 │   └── ...
-├── aviary_3/
+├── dev_aviary_3/
 │   └── ...
-├── aviary_4/
+├── dev_aviary_4/
 │   └── ...
-├── aviary_5/
+├── dev_aviary_5/
 │   └── ...
-├── aviary_6/
+├── dev_aviary_6/
 │   └── ...
 └── metadata/
     ├── ground_truth.csv
@@ -110,6 +110,7 @@ rec_{day}_{HH}_{MM}_{SS}[.ffffff].wav
 
 where `{day}` is a day identifier (`d1`, `d2`, or `d3`) and `{HH}_{MM}_{SS}[.ffffff]` encodes the time of day (hours, minutes, seconds, optional fractional seconds). For example, `rec_d1_19_05_02.500000.wav` is a recording from day 1 at 19:05:02.5.
 
+Day identifiers are anonymized — the mapping from day identifiers to calendar dates is not provided to participants.
 
 ### Chunk subdirectories
 
@@ -123,7 +124,7 @@ Complete species inventory for all 6 aviaries, including both target and non-tar
 
 | Column | Description |
 |---|---|
-| `aviary_id` | Aviary identifier (`aviary_1` through `aviary_6`) |
+| `aviary_id` | Aviary identifier (`dev_aviary_1` through `dev_aviary_6`) |
 | `common_name` | English common name of the species |
 | `scientific_name` | Binomial scientific name |
 | `count` | Number of individuals present in the aviary |
@@ -151,7 +152,7 @@ A complete baseline system is available at [https://github.com/ml4biodiversity/b
 
 3. **Population estimation** — Fit species-specific regression models using leave-one-out cross-validation.
 
-The baseline achieves a combined MAE of 11.50 (MAPE 10.6%.) across all target species using ARIA detections.
+The baseline achieves a combined MAE of 11.77 (MAPE 11.4%) across all target species using ARIA detections.
 
 ## Evaluation
 
@@ -186,9 +187,9 @@ git clone https://huggingface.co/datasets/Emreargin/BioDCASE2026_Bird_Counting
 
 # Run the baseline
 cd biodcase-population-estimation
-pip install aria-inference # or for faster and simpler detector -> pip install aria-inference-birdnet 
-aria-inference --input ../BioDCASE2026_Bird_Counting/aviary_1/ --output detections/aviary_1_detections.csv
-# ... repeat for aviary_2 through aviary_6
+pip install aria-inference
+aria-inference --input ../BioDCASE2026_Bird_Counting/dev_aviary_1/ --output detections/dev_aviary_1_detections.csv
+# ... repeat for dev_aviary_2 through dev_aviary_6
 python feature_builder.py --detections-dir detections/ --audio-root ../BioDCASE2026_Bird_Counting/ --output results/stage2_features.csv
 python estimator.py --features results/stage2_features.csv
 ```
@@ -216,6 +217,6 @@ If you use this dataset, please cite:
 For questions about the dataset or the challenge task, please contact:
 - **Emre Argın** — Maastricht University ([challenge task lead](https://biodcase.github.io/challenge2026/))
 - **Aki Härmä** — Maastricht University
-- **Aysenur Arslan-Dogan** — Maastricht University (main contact person) 
+- **Aysenur Arslan-Dogan** — Maastricht University
 
 Or open a discussion on the [dataset page](https://huggingface.co/datasets/Emreargin/BioDCASE2026_Bird_Counting/discussions).