Using RMarkdown
- Use
.mdfiles for episodes when you want static content - Use
.Rmdfiles for episodes when you need to generate output - Run
sandpaper::check_lesson()to identify any issues with your lesson - Run
sandpaper::build_lesson()to preview your lesson locally
Define terms and familiarize with the data
Decomposition is a process that breaks down a time series dataset into different componsents to identify patterns and variations. This helps with predicting (or forecasting) future data points, finding trends, and identifying anomalies in the data (outliers).
Trends in time series occur when there is an overall direction of the data. For example, when the data is increasing, decreasing, or remains constant over time. Outliers are single data points that go far outside the average value of a group of statistics.
In addition to trends, time series data may have other qualities: Seasonality: A regularly repeating pattern of highs and lows related to regular calendar periods such as seasons, quarters, months, or days of the week Cycles: A series of fluctuations that occur over a long period of time, usually multiple years or decades Variation: A change or difference in condition, amount, or level. Often separated into short or long term variation. Stationarity: A times series is considered to be stationarity when the statistical properties do not depend on a time at which the series is observed (there is no temporal trend in the data)
Some other terms to be aware of when working with time series: Missing values: Instances where a value for a specific variable is not recorded or available for a particular observation in a dataset (often recorded as NA or N/A or blank cells)
For our purposes, Non-perennial streams are rivers and streams that cease to flow at some point in time or space and are also commonly referred to as intermittent rivers and ephemeral streams (IRES).
A watershed is an area of land that separates water flowing to different rivers, basins, lakes, or the sea. Groundwater is freshwater that is stored in and orginiates from the ground between soil and rocks. Surfacewater is freshwater found on top fo land in a lake, river, stream, or pond.