Lære Introduction to Time Series Patterns

Sveip for å vise menyen

Time series data is a sequence of data points collected or recorded at successive points in time, usually at uniform intervals. This type of data is commonly encountered in fields such as finance, meteorology, and economics. Understanding the structure of time series data is crucial for effective analysis and forecasting.

There are three fundamental components often observed in time series data:

Trend: the long-term increase or decrease in the data. Trends show the general direction the data is moving over a period of time;
Seasonality: recurring patterns or cycles in the data that occur at regular intervals, such as daily, monthly, or yearly effects;
Noise: random variation or irregular fluctuations in the data that cannot be attributed to trend or seasonality.

Recognizing these components helps you interpret time series data and build better models for prediction and analysis.


              1234567891011121314151617181920212223242526272829303132
            
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt

# Generate a date range
dates = pd.date_range(start="2020-01-01", periods=120, freq="ME")

# Create a linear trend
trend = np.linspace(10, 50, 120)

# Add a seasonal component (annual seasonality)
seasonality = 10 * np.sin(2 * np.pi * dates.month / 12)

# Add random noise
np.random.seed(0)
noise = np.random.normal(0, 2, 120)

# Combine components to create the synthetic time series
synthetic_series = trend + seasonality + noise

# Create a pandas Series
time_series = pd.Series(synthetic_series, index=dates)

# Plot the time series
plt.figure(figsize=(12, 6))
plt.plot(time_series, label="Synthetic Time Series")
plt.title("Synthetic Time Series with Trend and Seasonality")
plt.xlabel("Date")
plt.ylabel("Value")
plt.legend()
plt.tight_layout()
plt.show()

When you examine the generated plot, you can visually identify the trend as a steady upward movement over time, indicating that the values generally increase from left to right. The seasonality appears as repeating waves or cycles superimposed on the trend, with peaks and troughs occurring at regular intervals. These patterns help you distinguish between systematic changes and random noise, making it easier to analyze and interpret the underlying structure of time series data.

Alt var klart?

Takk for tilbakemeldingene dine!

Seksjon 1. Kapittel 1

Spør AI

Spør om hva du vil, eller prøv ett av de foreslåtte spørsmålene for å starte chatten vår

Seksjon 1. Kapittel 1