rdtools.degradation.degradation_ols
- rdtools.degradation.degradation_ols(energy_normalized, confidence_level=68.2)
Estimate the trend of a timeseries using ordinary least-squares regression and calculate various statistics including a Monte Carlo-derived confidence interval of slope.
- Parameters:
energy_normalized (pandas.Series) -- Daily or lower frequency time series of normalized system ouput.
confidence_level (float, default 68.2) -- The size of the confidence interval to return, in percent.
- Returns:
Rd_pct (float) -- Estimated degradation relative to the year 0 system capacity [%/year]
Rd_CI (numpy.array) -- The calculated confidence interval bounds.
calc_info (dict) -- A dict that contains slope, intercept, root mean square error of regression ('rmse'), standard error of the slope ('slope_stderr'), intercept ('intercept_stderr'), and least squares RegressionResults object ('ols_results')