Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Performance of long short-term memory artificial neural networks in
  nowcasting during the COVID-19 crisis   The COVID-19 pandemic has demonstrated the increasing need of policymakers
for timely estimates of macroeconomic variables. A prior UNCTAD research paper
examined the suitability of long short-term memory artificial neural networks
(LSTM) for performing economic nowcasting of this nature. Here, the LSTM's
performance during the COVID-19 pandemic is compared and contrasted with that
of the dynamic factor model (DFM), a commonly used methodology in the field.
Three separate variables, global merchandise export values and volumes and
global services exports, were nowcast with actual data vintages and performance
evaluated for the second, third, and fourth quarters of 2020 and the first and
second quarters of 2021. In terms of both mean absolute error and root mean
square error, the LSTM obtained better performance in two-thirds of
variable/quarter combinations, as well as displayed more gradual forecast
evolutions with more consistent narratives and smaller revisions. Additionally,
a methodology to introduce interpretability to LSTMs is introduced and made
available in the accompanying nowcast_lstm Python library, which is now also
available in R, MATLAB, and Julia.

0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom