update: more accurate short-term prediction

This commit is contained in:
alikia2x (寒寒) 2025-03-15 04:19:04 +08:00
parent f0148ec444
commit a6211782cb
Signed by: alikia2x
GPG Key ID: 56209E0CCD8420C6
3 changed files with 83 additions and 53 deletions

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@ -1,6 +1,7 @@
import os
import json
import random
import bisect
import numpy as np
import pandas as pd
import torch
@ -8,51 +9,69 @@ from torch.utils.data import Dataset
import datetime
class VideoPlayDataset(Dataset):
def __init__(self, data_dir, publish_time_path, term = 'long'):
def __init__(self, data_dir, publish_time_path, term='long'):
self.data_dir = data_dir
self.series_dict = self._load_and_process_data(publish_time_path)
self.valid_series = [s for s in self.series_dict.values() if len(s['abs_time']) > 1]
self.term = term
# Set time window based on term
self.time_window = 1000 * 24 * 3600 if term == 'long' else 7 * 24 * 3600
if term == 'long':
self.feature_windows = [3600, 6*3600, 24*3600, 3*24*3600, 7*24*3600, 30*24*3600, 100*24*3600]
else:
self.feature_windows = [3600, 6*3600, 12*3600, 24*3600, 3*24*3600, 7*24*3600, 60*24*3600]
self.feature_windows = [
(3600, 0), (7200, 3600), (10800, 7200), (10800, 0),
(21600, 10800), (21600, 0), (64800, 43200), (86400, 21600),
(86400, 0), (172800, 86400), (259200, 0), (345600, 86400),
(604800, 0)
]
def _extract_features(self, series, current_idx, target_idx):
"""Extract incremental features"""
current_time = series['abs_time'][current_idx]
current_play = series['play_count'][current_idx]
dt = datetime.datetime.fromtimestamp(current_time)
if self.term == 'long':
time_features = [
np.log2(max(current_time - series['create_time'],1))
np.log2(max(current_time - series['create_time'], 1))
]
else:
time_features = [
(dt.hour * 3600 + dt.minute * 60 + dt.second) / 86400, (dt.weekday() * 24 + dt.hour) / 168,
np.log2(max(current_time - series['create_time'],1))
(dt.hour * 3600 + dt.minute * 60 + dt.second) / 86400,
(dt.weekday() * 24 + dt.hour) / 168,
np.log2(max(current_time - series['create_time'], 1))
]
# Window growth features (incremental)
growth_features = []
for window in self.feature_windows:
prev_time = current_time - window
prev_idx = self._get_nearest_value(series, prev_time, current_idx)
if prev_idx is not None:
time_diff = current_time - series['abs_time'][prev_idx]
play_diff = current_play - series['play_count'][prev_idx]
scaled_diff = play_diff / (time_diff / window) if time_diff > 0 else 0.0
else:
scaled_diff = 0.0
growth_features.append(np.log2(max(scaled_diff,1)))
if self.term == 'long':
for window in self.feature_windows:
prev_time = current_time - window
prev_idx = self._get_nearest_value(series, prev_time, current_idx)
if prev_idx is not None:
time_diff = current_time - series['abs_time'][prev_idx]
play_diff = current_play - series['play_count'][prev_idx]
scaled_diff = play_diff / (time_diff / window) if time_diff > 0 else 0.0
else:
scaled_diff = 0.0
growth_features.append(np.log2(max(scaled_diff, 1)))
else:
for window_start, window_end in self.feature_windows:
prev_time_start = current_time - window_start
prev_time_end = current_time - window_end # window_end is typically 0
prev_idx_start = self._get_nearest_value(series, prev_time_start, current_idx)
prev_idx_end = self._get_nearest_value(series, prev_time_end, current_idx)
if prev_idx_start is not None and prev_idx_end is not None:
time_diff = series['abs_time'][prev_idx_end] - series['abs_time'][prev_idx_start]
play_diff = series['play_count'][prev_idx_end] - series['play_count'][prev_idx_start]
scaled_diff = play_diff / (time_diff / (window_start - window_end)) if time_diff > 0 else 0.0
else:
scaled_diff = 0.0
growth_features.append(np.log2(max(scaled_diff, 1)))
time_diff = series['abs_time'][target_idx] - series['abs_time'][current_idx]
return [np.log2(max(time_diff,1))] + [np.log2(current_play + 1)] + growth_features + time_features
time_diff = series['abs_time'][target_idx] - current_time
return [np.log2(max(time_diff, 1))] + [np.log2(current_play + 1)] + growth_features + time_features
def _load_and_process_data(self, publish_time_path):
# Load publish time data
publish_df = pd.read_csv(publish_time_path)
publish_df['published_at'] = pd.to_datetime(publish_df['published_at'])
publish_dict = dict(zip(publish_df['aid'], publish_df['published_at']))
@ -75,42 +94,53 @@ class VideoPlayDataset(Dataset):
}
series_dict[aid]['abs_time'].append(item['added'])
series_dict[aid]['play_count'].append(item['view'])
# Sort each series by absolute time
for aid in series_dict:
sorted_indices = sorted(range(len(series_dict[aid]['abs_time'])),
key=lambda k: series_dict[aid]['abs_time'][k])
series_dict[aid]['abs_time'] = [series_dict[aid]['abs_time'][i] for i in sorted_indices]
series_dict[aid]['play_count'] = [series_dict[aid]['play_count'][i] for i in sorted_indices]
return series_dict
def __len__(self):
return 100000 # Use virtual length for infinite sampling
return 100000 # Virtual length for sampling
def _get_nearest_value(self, series, target_time, current_idx):
"""Get the nearest data point before the specified time"""
min_diff = float('inf')
for i in range(current_idx + 1, len(series['abs_time'])):
diff = abs(series['abs_time'][i] - target_time)
if diff < min_diff:
min_diff = diff
else:
return i - 1
return len(series['abs_time']) - 1
times = series['abs_time']
pos = bisect.bisect_right(times, target_time, 0, current_idx + 1)
candidates = []
if pos > 0:
candidates.append(pos - 1)
if pos <= current_idx:
candidates.append(pos)
if not candidates:
return None
closest_idx = min(candidates, key=lambda i: abs(times[i] - target_time))
return closest_idx
def __getitem__(self, _idx):
series = random.choice(self.valid_series)
current_idx = random.randint(0, len(series['abs_time'])-2)
if self.term == 'long':
range_length = 50
else:
range_length = 10
target_idx = random.randint(max(0, current_idx-range_length), current_idx)
# Extract features
features = self._extract_features(series, current_idx, target_idx)
# Target value: future play count increment
while True:
series = random.choice(self.valid_series)
if len(series['abs_time']) < 2:
continue
current_idx = random.randint(0, len(series['abs_time']) - 2)
current_time = series['abs_time'][current_idx]
max_target_time = current_time + self.time_window
candidate_indices = []
for j in range(current_idx + 1, len(series['abs_time'])):
if series['abs_time'][j] > max_target_time:
break
candidate_indices.append(j)
if not candidate_indices:
continue
target_idx = random.choice(candidate_indices)
break
current_play = series['play_count'][current_idx]
target_play = series['play_count'][target_idx]
target_delta = max(target_play - current_play, 0) # Increment
target_delta = max(target_play - current_play, 0)
return {
'features': torch.FloatTensor(features),
'target': torch.log2(torch.FloatTensor([target_delta]) + 1) # Output increment
'features': torch.FloatTensor(self._extract_features(series, current_idx, target_idx)),
'target': torch.log2(torch.FloatTensor([target_delta]) + 1)
}
def collate_fn(batch):

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@ -4,19 +4,19 @@ from model import CompactPredictor
import torch
def main():
model = CompactPredictor(12).to('cpu', dtype=torch.float32)
model.load_state_dict(torch.load('./pred/checkpoints/model_20250315_0226.pt'))
model = CompactPredictor(18).to('cpu', dtype=torch.float32)
model.load_state_dict(torch.load('./pred/checkpoints/model_20250315_0407.pt'))
model.eval()
# inference
initial = 999469
last = initial
start_time = '2025-03-11 15:03:31'
for i in range(1, 32):
for i in range(1, 64):
hour = i / 4.2342
sec = hour * 3600
time_d = np.log2(sec)
data = [time_d, np.log2(initial+1), # time_delta, current_views
6.319254, 9.0611, 9.401403, 10.653134, 12.008604, 13.230796, 16.3302, # grows_feat
6.319244, 6.96288, 7.04251, 8.38551, 7.648974, 9.061098, 9.147728, 10.07276, 10.653134, 10.092601, 12.008604, 11.676683, 13.230796, # grows_feat
0.627442, 0.232492, 24.778674 # time_feat
]
np_arr = np.array([data])

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@ -11,7 +11,7 @@ def train(model, dataloader, device, epochs=100):
writer = SummaryWriter(f'./pred/runs/play_predictor_{time.strftime("%Y%m%d_%H%M")}')
optimizer = torch.optim.AdamW(model.parameters(), lr=1e-3, weight_decay=0.01)
scheduler = torch.optim.lr_scheduler.OneCycleLR(optimizer, max_lr=1e-3,
total_steps=len(dataloader)*epochs)
total_steps=len(dataloader)*30)
criterion = torch.nn.MSELoss()
model.train()
@ -82,7 +82,7 @@ if __name__ == "__main__":
input_size = sample['features'].shape[1]
model = CompactPredictor(input_size).to(device)
trained_model = train(model, dataloader, device, epochs=30)
trained_model = train(model, dataloader, device, epochs=18)
# Save model
torch.save(trained_model.state_dict(), f"./pred/checkpoints/model_{time.strftime('%Y%m%d_%H%M')}.pt")