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Feature overview table

Note that all catch22 features are statistical properties of the z-scored time series—they aim to focus on properties of the time-ordering of the data and are insensitive to the raw values in the time series.
In the table below we give the original feature name [from the Lubba et al. (2019) paper], and a shorter name more suitable for use in feature descriptions.
Features are also (loosely) categorized into broad conceptual groupings.
#
Feature name
Short name
Category
Description
1
DN_HistogramMode_5
mode_5
5-bin histogram mode
2
DN_HistogramMode_10
mode_10
10-bin histogram mode
3
DN_OutlierInclude_p_001_mdrmd
outlier_timing_pos
Positive outlier timing
4
DN_OutlierInclude_n_001_mdrmd
outlier_timing_neg
Negative outlier timing
5
first1e_acf_tau
acf_timescale
First
1/e1/e
crossing of the ACF
6
firstMin_acf
acf_first_min
First minimum of the ACF
7
SP_Summaries_welch_rect_area_5_1
low_freq_power
Power in lowest 20% frequencies
8
SP_Summaries_welch_rect_centroid
centroid_freq
Centroid frequency
9
FC_LocalSimple_mean3_stderr
forecast_error
Error of 3-point rolling mean forecast
10
FC_LocalSimple_mean1_tauresrat
whiten_timescale
Change in autocorrelation timescale after incremental differencing
11
MD_hrv_classic_pnn40
high_fluctuation
Proportion of high incremental changes in the series
12
SB_BinaryStats_mean_longstretch1
stretch_high
Symbolic
Longest stretch of above-mean values
13
SB_BinaryStats_diff_longstretch0
stretch_decreasing
Symbolic
Longest stretch of decreasing values
14
SB_MotifThree_quantile_hh
entropy_pairs
Symbolic
Entropy of successive pairs in symbolized series
15
CO_HistogramAMI_even_2_5
ami2
Histogram-based automutual information (lag 2, 5 bins)
16
CO_trev_1_num
trev
Time reversibility
17
IN_AutoMutualInfoStats_40_gaussian_fmmi
ami_timescale
First minimum of the AMI function
18
SB_TransitionMatrix_3ac_sumdiagcov
transition_variance
Symbolic
Transition matrix column variance
19
PD_PeriodicityWang_th001
periodicity
Wang's periodicity metric
20
CO_Embed2_Dist_tau_d_expfit_meandiff
embedding_dist
Other
Goodness of exponential fit to embedding distance distribution
21
SC_FluctAnal_2_rsrangefit_50_1_logi_prop_r1
rs_range
Rescaled range fluctuation analysis (low-scale scaling)
22
SC_FluctAnal_2_dfa_50_1_2_logi_prop_r1
dfa
Detrended fluctuation analysis (low-scale scaling)
And in some cases, in which scale and spread of the raw time-series values may be relevant to class differences, the two simple distributional moment features (using the catch24 flag in the software implemenations) can be added:
Feature name
Short name
Description
DN_Mean
mean
Mean
DN_Spread_Std
std
Standard deviation