<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <article-id pub-id-type="doi">10.1007/978</article-id>
      <title-group>
        <article-title>Correction to Operationalize Movement Trajectory Classification</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Bowen Xi</string-name>
          <email>bowenxi@asu.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Kevin Scaria</string-name>
          <email>kscaria@asu.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Divyagna Bavikadi</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Paulo Shakarian</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Arizona State University</institution>
          ,
          <addr-line>Tempe, Arizona</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Syracuse University</institution>
          ,
          <addr-line>Syracuse</addr-line>
          ,
          <country>New York</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2025</year>
      </pub-date>
      <abstract>
        <p>Classification of movement trajectories has many applications in transportation and is a key component for largescale movement trajectory generation and anomaly detection which has key safety applications in environments with unseen movement types. However, the current state-of-the-art (SOTA) are based on supervised deep learning - which leads to challenges when they encounter novel unseen classes. We provide a neuro-symbolic rule-based framework to conduct error correction and detection of these models to integrate into our movement trajectory platform. We provide a suite of experiments on several recent SOTA models where we show highly accurate error detection, the ability to improve accuracy on test data that includes novel movement types not seen in training set, and accuracy improvement for the base use case in addition to a suite of theoretical properties that informed algorithm development. Specifically, we show an F1 scores for predicting errors of up to significant performance increase for unseen movement accuracy ( 8.51% improvement over SOTA for zero-shot accuracy), and accuracy improvement over the SOTA model.</p>
      </abstract>
      <kwd-group>
        <kwd>Classification</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>0.984,</p>
    </sec>
    <sec id="sec-2">
      <title>1. Introduction</title>
      <p>ISSN1613-0073</p>
      <p>
        In what follows, we provide further background on our domain problem and our current trajectory
analysis platform (some of which is a review of [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]), introduce the algorithmic framework for EDCR
including it’s theoretical properties, and provide our suite of experimental results before concluding
with our findings and future work.
      </p>
    </sec>
    <sec id="sec-3">
      <title>2. Background</title>
      <p>
        Overall concept and deployed system. Movement types not typically included in the ground truth
data emerge with certain target environments (e.g, paid scooters in certain urban areas, auto-rickshaws
in South Asia, or boats in Venice). As a result, IARPA (Intelligence Advanced Research Projects Activity)
has identified problems relating to the characterization and generation of normal movement as a key
problem of study in the HAYSTAC program. Here, the goal is to establish models of normal human
movement at a fine-grain level and operationalize those models and techniques in a system deployed to
a government environment for evaluation. As a performer on the program, [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] examine the problem of
generating realistic movement trajectories.
      </p>
      <p>Initial government tests for trajectory generation involved movement trajectories consisting of only
a single mode of transportation. However, in preparation for the transition to operational use, the
government has set requirements to analyze trajectories from various movement types - where the mode
of transportation is not known. As such, we look to operationalize a movement trajectory classification
module, which we have depicted in the context of our deployed cloud-based architecture shown in
Figure 1.</p>
      <p>
        This pipeline interfaces with the government system to access the raw geospatial data with related
knowledge for various geolocations as well as historical agent trajectories and their corresponding
objective files. Our initial ingest and containerized processes are held in a directed acyclic graph
(DAG) as nodes. Our ingest mechanism first parses for the historical trajectories associated with a
given agent to stage them in the S3 bucket. Then, geospatial data stored in Neo4j is consolidated
into a knowledge graph and staged into the S3 bucket. We instantiate pods on the Amazon Elastic
Kubernetes Service (EKS) cluster for all agents with a Docker image to analyze the staging folders
and create the respective string commands specific to each agent. The trajectory classification module
identifies and tags the modes of transportation in the corresponding trajectory, which is further used
to learn rules while considering diferent types of movements. These rules along with the knowledge
graph are used to compute the heuristic value for an informed search method (A* search) to generate
movement trajectories [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. As the container runs, generated movement instruction files are pushed to
the appropriate output directory as seen in Figure 1. Additionally, the generated movement abides by
predefined spatiotemporal constraints (objectives).
      </p>
      <p>
        Movement Trajectory Classification Problem. The problem of classifying movement trajectories
has been studied in the literature [
        <xref ref-type="bibr" rid="ref4 ref5 ref7 ref8 ref9">7, 8, 9, 5, 4</xref>
        ] and we shall refer to it as the movement trajectory
classification problem (MTCP). We also note that this line of work difers from and is complementary
to trajectory generation [
        <xref ref-type="bibr" rid="ref10 ref11 ref12 ref6">6, 10, 11, 12</xref>
        ] which does not seek to identify the mode of transportation. An
MTCP instance is defined as given a sequence of GPS points,  , assign one of  movement class from 
which is often defined [
        <xref ref-type="bibr" rid="ref4 ref5">4, 5</xref>
        ] as  = { walk, bike, bus, drive, train}.
      </p>
      <p>
        The current paradigm for the MTCP problem is to create a neural model   that maps sequences
to movement classes using a set of weights,  . In this approach traditional methods (i.e., gradient
descent) are used to find a set of parameters such that a loss function is minimized based on some
training set  (where each sample  ∈  is associated with a ground truth class () ). Formally:
arg min  ∈ Loss(  (), ()) . Within this paradigm, several approaches have been proposed. Most
notably a CNN-based architecture [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] and the current state-of-the-art approach known as Long-term
Recurrent Convolutional Network (LRCN) [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] which combines lower CNN layers and upper LSTM
layers - both of which we use as baselines in addition to an extension of LRCN that uses an additional
attention head (LRCNa).
      </p>
      <p>Limitations of Current SOTA. However, there are several limitations to these approaches that are
problematic in the context of the IARPA HAYSTAC use case.</p>
      <p>
        • Not designed for unseen movements. Any supervised MTCP model requires a data set whose
movement classes match the target environment. To address the more dynamic needs of our
government customer, we require approaches that can identify when they are likely to give
incorrect results to adapt to novel environments.
• All classes known a-priori. In the prior work, set  is treated as static and complete meaning that
novel movement types not in training set will not be properly classified and not identified as
being diferent than a movement type in class  .
• Previous Results Evaluated on Overlapping Training and Testing Sets. As noted in [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], the standard
evaluation of MTCP approaches has been on datasets that experience leakage between train and
test. Due to the operational nature of this work, we must examine other splits.
      </p>
      <p>
        Deploying movement trajectory classification models to a certain environments can lead to movements
not seen in training (e.g., paid scooters are not seen in training but prevalent in certain urban areas).
Hence, these “novel movements” will inherently be classified incorrectly. The common element in
all of these limitations is an understanding of when such classifiers are likely wrong. However, this
goes beyond retraining or selecting from diferent training data as the government customer envisions
use-cases with unseen movement types- hence training data would be limited. This generally precludes
meta-learning and domain generalization [
        <xref ref-type="bibr" rid="ref14 ref15 ref16 ref17">14, 15, 16, 17</xref>
        ] which attempt to account for changes in the
distribution of data and/or selection of a model that was trained on data similar to the current problem.
This work also difers from approached like One-Class Support Vector Machine [ 18] because of the
inherent rule-based method in EDCR that can be leveraged for explainability and can further be built
upon machine learning models.
      </p>
      <p>
        Additionally, these problems must also be addressed in the context of our existing system (Figure 1),
which employs symbolic reasoning to generate movement trajectories - ensuring they attain a degree
of normalcy [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. As a result, we examined approaches for characterizing failures in machine learning
models such as introspection [
        <xref ref-type="bibr" rid="ref18 ref19">19, 20</xref>
        ], however, these approaches only predict model failure and do
not attempt to explain or correct it. Another area of related work is machine learning verification
that [
        <xref ref-type="bibr" rid="ref20">21, 22, 23</xref>
        ]) that looks to ensure the output of an ML model meets a logical specification - however
to-date this work has not been applied to correct the output of a machine learning model and generally
depend on the logical specifications being known a-priori (not an assumption we could make for our use
case). In recent studies on abductive learning [24, 25] and neural symbolic reasoning [26], incorporate
error correction mechanisms rooted in inconsistency with domain knowledge as logical rules - but as
with verification, we do not have this symbolic knowledge a-priori.
      </p>
    </sec>
    <sec id="sec-4">
      <title>3. Error Detection and Correction Rules</title>
      <p>To address the issues of the previous section, we are employing a rule-based approach to correcting
MTCP model   . The intuition is that using limited data, we will learn a set of rules (denoted Π) that will
be able to detect and correct errors of   by logical reasoning [27]. Then, upon deployment for some
new sequence  , we would first compute the class   () and then use the rules in set Π to conclude if
the result of   should be accepted and if not, provide an alternate class in an attempt to correct the
mistake. In this section, we formalize the error correcting framework with a simple first order logic
(FOL) and provide analytical results relating aspects of learned rules that inform our analytical approach
to learning such error detecting and correcting rules. We complete the section with a discussion on
how various potential “failure conditions” are extracted to create the rules to correct errors.</p>
      <p>In this paper, we shall assume a set  of operational sequences for which there is ground truth
available after model training. This set can be the set of training data, a subset, or a superset. We
notate the set of training data with  . Later, in our experiments, we look at cases where  = 
and
 ⊆</p>
      <p>- however these are not requirements as our results are based on model performance on 
- and we envision use-cases where  is significantly diferent from
 . On these samples, for each
class  , the model (  ) returns class  for   of the samples, and for each class  we have the number of
true positives    , false positives  
 , true negatives    , and false negatives   
. We have precision
  =    /  =    /(   +    ), recall   =    /(   +  
 ), and prior of predicting class  :   =   / .</p>
      <p>Language. We use a simple first-order language where samples are represented by constant symbols
( ). We define set  of  “condition” unary predicates 
1, … , 
 associated with each sample that
can be either true or false - these are conditions that can be thought of as potentially leading to failure
(but our learning algorithms will identify which ones lead to failure for a given prediction). These
predicates can also be features related to a sample in the dataset. We also define unary predicates for
each class  :  
 ,    , and</p>
      <p>defined below.
•  
•  
•   
if () =  .
prediction.</p>
      <p>: True if and only if the model predicts class  i.e.,  
 () is true if 
 () =  .
 : This predicate is true if and only if the correct movement class for  is  , i.e.,  
 () is true
: This predicate is true if and only if an EDCR rule concludes there is an error in the model’s
Rules. The set of rules Π will consist of two rules for each class: one “error detecting” and one “error
correcting.” Error detecting rules which will determine if a prediction by   is not valid. In essence,
we can think of such a rule as changing the movement class assigned by   to some sample  from 
to “unknown.” For a given class  , we will have an associated set of detection conditions 
 that is a
subset of conditions, the disjunction of which is used to determine if   gave an incorrect classification.
   ()
based on a subset of conditions-class pairs 
are used to correct the class of a given sample.</p>
      <p>⊆  ×  . The disjunction of such condition-class pairs
(1)
(2)</p>
      <p>Support w.r.t. class  (  ): given the subset of samples where the model predicts class  , the fraction of
those samples where the body is true (note the denominator is   ).</p>
      <p>Confidence (  ): the number of times the body and head are true together divided by the number of times
the body is true.</p>
      <p>Now we present some analytical results that inform our learning algorithms. Our strategy for learning
involves first learning detection rules (which establish conditions for which a given classification decision
by   is deemed incorrect) and then learning correction rules (which then correct the detected errors by
assigning a new movement class to the sample). We formalize these two tasks as follows.
Improvement by error detecting rule. For a given class  , find a set of conditions   such that precision
is maximized and recall decreases by, at most  .</p>
      <p>Improvement by error correcting rule. For a given class  , find a subset   of  × 
such that both
precision and recall are maximized.
improvement in precision.2
Properties of Detection Rules. First, we examine the efect on precision and recall when an error
detecting rule is used. Our first result shows a bound on precision improvement. If class support (   )
is less than 1 −   , which we would expect (as the rule would be designed to detect the 1 −   portion
of results that failed), then we can also show that the quantity  ⋅   gives us an upper bound on the
Theorem 1. Consider an error detecting rule with support   and confidence  , initial precision   of model
  for class  , then under the condition   ≤ 1 −   , the precision of model   for class  , after applying the
error detecting rule increases by a function of both   and  . The increase is no greater than  ⋅   and this
quantity is a normalized polymatroid submodular function with respect to the set of conditions in the rule</p>
      <p>.</p>
      <p>The error detecting rules can cause the recall to stay the same or decrease. Our next result tells us
precisely how much recall will decrease.</p>
      <p>Theorem 2. After applying the rule to detect errors, the recall will decrease by (1 − ) 
is a normalized polymatroid submodular function with respect to the set of conditions in the rule  
.
 
  and this quantity</p>
      <sec id="sec-4-1">
        <title>Algorithm 1 DetRuleLearn</title>
        <p>Require: Class  , Recall reduction threshold  , Condition set 
Ensure: Subset of conditions  
  ∶= ∅

while 
∗ ∶= { ∈</p>
        <p>s.t.  


Add</p>
        <p>∗ ≠ ∅ do
= arg max∈
to</p>
        <p>∗ ∶= { ∈  ∖ 
end while
return  
{} ≤  ⋅     }</p>
        <p>∗</p>
        <p>∪{}
 s.t.  
  ∪{} ≤  ⋅     }</p>
        <p />
        <p>As the quantities identified Theorems 1 and 2 are submodular and monotonic, we can see that the
selection of a set of rules to maximize  ⋅   subject to the constraint that (1 − ) 
the “Submodular Cost Submodular Knapsack” (SCSK) problem and can be approximated with a simple
greedy algorithm [28] with approximation guarantee of polynomial run time (Theorem 4.7 of [28]).
Our algorithm DetRuleLearn is an instantiation of such an approach to creating an error detecting rule
for a given class that maximize precision while not reducing recall more than  . Here,  is treated as a
hyperparameter. Also,  

and</p>
        <p>for some set</p>
        <p>and are true errors (for  
set of condition class pairs and the rule of interest, 
are simply the number of samples that satisfy the conditions
 ) and non-errors (for</p>
        <p>). In other words, given a
here is the number of examples that satisfy the
 
  ≤  is a special case of</p>
        <sec id="sec-4-1-1">
          <title>2Complete proofs for all formal results can be found at</title>
          <p>body (class-condition pair) of the error detection rules, and  
here is the number of examples that
satisfy the body (class-condition pair) and the head of the error detection rules.   ,   are precision and
recall for class  while   is the number of samples that the model classifies as class  .
Properties of Corrective Rules. In what follows, we shall examine the results for corrective rules.
Here, the error correcting rule with predicate</p>
          <p>in the head will have a disjunction of elements of set
  ⊆  ×</p>
          <p>. Also, note that here the support  is used instead of class support (  ). Here we find that
both precision and recall increase with rule confidence (Theorem 3).</p>
          <p>Theorem 3. For the application of error correcting rules, both precision and recall increase if and only if
rule confidence (  ) increases.</p>
          <p>This result suggests that optimizing confidence will optimize both precision and recall. However,
this is not a monotonic function over   , so we adopt a fast, heuristic approach for non-monotonic
optimization based on [29], presented by CorrRuleLearn in this paper. Here, we will consider an initial
set of condition-class pairs 
error correcting rule, we select 
 that is a subset of  ×</p>
          <p>. For a given class for which we create an
 from this larger set using our approach. Note here that  

is the
number of samples that satisfy the rule body and head ( 
 () in this case) given a set of condition-class
pairs 
while</p>
          <p>is the number of samples that satisfy the body formed with set  .</p>
        </sec>
      </sec>
      <sec id="sec-4-2">
        <title>Algorithm 2 CorrRuleLearn</title>
        <p>Require: Class  , Set of condition-class pairs  
Ensure: Subset of condition-class pairs  
  ∶= ∅
 ′ ∶=  
for (, ) ∈ 
 ∶= 
 ∶= 
if  ≥ 


else
 ′ ∶=  ′ ∖ {(, )}</p>
        <p>selected in order of the sorted list do
Sort each (, ) ∈   from greatest to least by 
{(,)} and remove
{(,)}


{(,)}
{(,)} ≤  
Learning Detection and Correction Rules Together. Error correcting rules created using
CorrRuleLearn will provide optimal improvement to precision and recall for the rule in the target class, but in
the case of multi-class problems, it will cause recall to drop for some other classes. However, we can
combine error detecting and correcting rules to overcome this dificulty. The intuition is first to create
error detecting rules for each class, which efectively re-assigns any sample into an “unknown” class.
Then, we create a set   (used as input for CorrRuleLearn) based on the conditions selected by the
error detecting rules. In this way, we will not decrease recall beyond what occurs in the application of
is quadratic in the number of conditions and linear in the number of samples. However, in practice it
actually performs better, as the outer loop iterates significantly less than the total number of
conditions and the number of selected conditions is reduced with each iteration. Likewise, the algorithm
CorRuleLearn is linear in the number of samples and linear in the number of condition-class pairs.
error detecting rules.</p>
        <p>Algorithmic Eficiency.</p>
        <p>We note that these algorithms are quite eficient. For example,
DetRuleLearn</p>
      </sec>
      <sec id="sec-4-3">
        <title>Algorithm 3 DetCorrRuleLearn</title>
        <p>Require: Recall reduction threshold  , Condition set 
Ensure: Set of rules Π
Π ∶= ∅</p>
        <p>∶= ∅
for Each class  do
  ∶= DetRuleLearn(, , )
if   ≠ ∅ then
Π ∶= Π∪
{   ()
  ∶= CorrRuleLearn(,   )
if   ≠ ∅ then
Π ∶= Π∪
approaches to this. First, we use a binary version of the classifier – for given class  , we have a binary
classifier   which returns “true” for sample  if   assigns it as  and “false” otherwise. In this way, for
each sample  we have a   () condition for each of the classes. The second way we create conditions
is based on outlier behavior based on the velocity of the vehicle in the sample. Here, if the velocity of a
given sample is above a threshold (based on the maximum value for ground truth in the training data)
this velocity condition is true - and it is false otherwise.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>4. Experimental Evaluation</title>
      <p>
        Experimental Setup. Previous work such as [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] is known to have data leakage based on the split
between training and test primarily due to segments of a movement sequence existing in both training
and test sets [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. In this paper, we examine a training-test split with no overlap between the two
avoiding this error and more closely resembling our target use-case. The assessments in this paper used
GPS trajectories obtained from the GeoLife project [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] which include ground truth (note that ground
truth data for our target application was unavailable at the time of this writing). All experiments were
conducted on an NVIDIA A100 GPU using Python 3.10, with an 80/20 train–test split. Source code is
available via https://github.com/lab-v2/Error-Detection-and-Correction.
      </p>
      <p>
        Error Detection Experiments. First we examined the ability of learned error detection rules to detect
errors in the underlying model. Here we examined three base model architectures CNN [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], LRCN [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ],
and our version of LRCN with an additional attention head (LRCNa). In this experiment, error detection
rules were trained from the same training data as the model. Similar to previous work on examining
the ability to detect errors in a machine learning model [
        <xref ref-type="bibr" rid="ref18">19</xref>
        ] we evaluated precision, recall, and F1
of the ability of rules to identify errors. These can be thought of as the fraction of results where our
learned error detection rules correctly return an error (error precision), the fraction of errors identified
Evaluated
Model
LRANa
LRCN
CNN
(EDCR)
consistently high precision and recall for detecting errors across all model types - specifically obtaining
a 0.875 F1 for errors in the SOTA model (LRCN) and a top F1 of 0.984 (for CNN).
      </p>
      <p>Test Data with Additional Classes. A key set of concerns for our use-case was the ability to deploy
movement trajectory classification in an environment where the data difers from the training data
- specifically containing previously unidentified classes. To examine this, we trained CNN, LRCN,
and LRCNa models without incorporating the walk and drive classes (Figure 2). We note here both
detection and correction are used. We initially learned the EDCR rules with the same training data in
the model - which results in no sample being corrected to a class unseen in training data and efectively
is zero-shot tuning of the base model by EDCR. However, due to detection, this still resulted in accuracy
improvements of 6.41%, 8.51%, and 7.76% for LRCNa, LRCN, and CNN respectively. We then added
few-shot samples from the unseen data (the x-axis of Figure 2) giving us few-shot tuning of the base
model. Here with only 20% of the samples with the unseen classes, we obtained an overall accuracy
of 0.65 on all three models representing a 17 − 18% improvement. We note these results are obtained
without direct access to the underlying model, which may indicate that EDCR has the potential for
adaptation of arbitrary   models to novel scenarios - a key use case for our government customer.
Precision-Recall Trade-of.</p>
      <p>A key intuition in our algorithmic design with the ability for the
hyperparameter to  to trade-of precision and recall. Hence, we examined the efect in varying

on test data that resembled training data (results for LRCN are shown in Figure 3). Recall that  is
interpreted as the maximum decrease in recall. We observed and validated the theoretical reduction
(TR) in recall empirically and the experiments show us that in all cases, recall was no lower than the
threshold specified by the hyperparameter  though recall decreases as  increases. In many cases, the
experimental evaluation reduced recall significantly less than expected. We also see a clear relationship
between  , precision, and recall: increasing  leads to increased precision and decreased recall - which
also aligns with our analytical results. We also note that while DetCorrRuleLearn calls for a single 
hyperparameter, it is possible to set it diferently for each class (e.g., lower values for classes where
recall is important, higher values for classes where false positives are expensive). This may be beneficial
as F1 for diferent classes seemed to peak for diferent values of
 . We leave the study of heterogeneous
 settings to future work.</p>
      <p>Evaluated
Model
LRCNa
LRCN
CNN</p>
      <p>No EDCR
(baseline)</p>
      <p>Accuracy Improvement via EDCR. We also investigated EDCR’s ability to provide overall accuracy
improvement to the base model. Here we trained each of the three models (LRCNa, LRCN, CNN) and
associated EDCR rules (on the same training data as the model) and evaluated the overall accuracy on
the test set both with and without applying rules (see Table 3). We found that that EDCR provided
a noticeable improvement in both LRCN and LRCNa models - efectively establishing a new SOTA
when evaluated with no overlap between training and testing. We also examined other splits between
training and testing (not depicted) and obtained comparable results.</p>
    </sec>
    <sec id="sec-6">
      <title>5. Conclusion</title>
      <p>We propose a rule-based framework for the error detection and correction of supervised neural models
for classification of movement trajectories. Our framework uses the training data to learn rules to be
employed in the testing phase. Firstly, we use the detection rules to identify the movement trajectories
that are misclassified by the supervised model and then we use the correction rules to re-classify the
movement. Further, we formally prove the relation of confidence and support of the learned rules to
the changes in the classification metrics like precision and recall. To show EDCR’s emperical validation,
we first report the framework’s ability to identify errors with the F1 scores going up to 0.984. We also
show overall accuracy imporvement over the SOTA model by employing the EDCR framework. Our
framework is specifically useful in cases of encountering novel classes not seen in training data as shown
by a 8.51% improvement of unseen movement accuracy over SOTA for zero-shot tuning. Additionally,
we discuss operationalizing our trajectory classification method in our deployed system. There are
several directions for future work. First, we look to explore other methods to create the conditions, in
particular leveraging ideas from conformal prediction [30]. Another direction is to look at alternative
solutions to learn the rules allowing for more complicated rule structures. Human validation of the
rules responsible for a corrected label can be conducted for further evaluation. Finally, the use of rules
for error detection and correction of machine learning models presented here may be useful in domains
such as vision. To reliably incorporate vision models in real-world applications for tasks like object
detection, image classification, and motion tracking, etc., EDCR framework can be leveraged to improve
the overall system’s accuracy and robustness by identifying and correcting it’s misclassification.</p>
    </sec>
    <sec id="sec-7">
      <title>Ethical Statement</title>
      <p>There are no ethical issues.</p>
    </sec>
    <sec id="sec-8">
      <title>6. Acknowledgments</title>
      <p>This research is supported by the Intelligence Advanced Research Projects Activity (IARPA) via the
Department of Interior/ Interior Business Center (DOI/IBC) contract number 140D0423C0032. The U.S.
Government is authorized to reproduce and distribute reprints for Governmental purposes
notwithstanding any copyright annotation thereon. Disclaimer: The views and conclusions contained herein
are those of the authors and should not be interpreted as necessarily representing the oficial policies or
endorsements, either expressed or implied, of IARPA, DOI/IBC, or the U.S. Government. Additionally,
some of the authors are supported by ONR grant N00014-23-1-2580 and ARO grant W911NF-24-1-0007.</p>
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check. After using this tool/service, the author(s) reviewed and edited the content as needed and take(s)
full responsibility for the publication’s content.</p>
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    <sec id="sec-10">
      <title>A. Appendix</title>
      <p>A.1. Proof of Theorem 1
Under the condition   ≤ 1 −   , the precision of model   for class  , with initial precision   , after
applying an error detecting rule with support   and confidence  increases by a function of   and  and
is no greater than  ⋅   and this quantity a normalized polymatroid submodular function with respect to
the set of conditions in the rule</p>
      <p>.</p>
      <p>Proof. CLAIM 1: The precision of model   for class  , with initial precision   , after applying an error
detecting rule with support   and confidence  increases by:


1 −  
( +   − 1)
(3)
The total number of items that   will attempt to classify as  before error detection is   =    +    .
Out of those,   ⋅   will be detected by the rule. However, a fraction of (1 − ) will be samples that would
have been true positives if not detected. Hence, the new precision can be written as follows:
As   ⋅   =    , we have:
Now we subtract from that quantity the initial precision.</p>
      <p>− (1 − )  ⋅</p>
      <p>−   ⋅  
  ⋅   − (1 − )  ⋅  
  (1 −   )
=   − (1 − )</p>
      <p>(1 −   )
  − (1 − )  −</p>
      <p>(1 −   )
=   − (1 − )  −
(1 −   )
(1 −   ) 
∈
CLAIM 2: If   ≤ 1 −   then  ⋅   is a upper bound on the improvement in precision.</p>
      <p>BWOC, then by Claim 1 we have.</p>
      <p>However, as  ≤ 1 this is a contradiction.</p>
      <p>CLAIM 3:  ⋅   = /</p>
      <p>where 
satisfied.</p>
      <p>Let 
is equivalent to the statement of the claim.</p>
      <p>CLAIM 4: The quantity  ⋅   is submodular w.r.t. set  .</p>
      <p>We show this by the submodularity of 
We can re-write (
1 ∪  1) as:</p>
      <p>is the number of samples where both the rule body and head are
be the number of samples that the body of the rule is true. This gives us  ⋅   = 


 
which
as   is a constant as well as the result of Claim 3. BWOC,
is not submodular for some set</p>
      <p>. We use the symbol ()
existence of two sets of conditions  1,  2. Then, the following must be true:
to denote this and assume the
Substituting this back into inequality 16, we can re-write the right-hand side as:
=
=
 (
 (
 (
Which give us our contradiction.</p>
      <p>CLAIM 5:  ⋅   monotonically increases with  .</p>
      <p>By claim 1, as the quantity equals  /  and   is a constant, we just need to show monotonicity of
  . Clearly   increases monotonically as additional elements in  can only make it increase.
CLAIM 6: When  = ∅ ,  ⋅   = 0.</p>
      <p>Follows directly from the fact that we define   as zero is no conditions are used.</p>
      <p>Proof of theorem. Follows directly from claims 1-6.</p>
      <p>A.2. Proof of Theorem 2
After applying the rule to detect errors, the recall will decrease by (1 − )    and this quantity is a
normalized polymatroid submodular function with respect to the set of conditions in the rule   .
Proof. CLAIM 1: After applying the rule to detect errors, the recall will decrease by (1 − )    .
The number of corrections made by the rule is   (   +    ) with (1 − ) fraction of these being incorrect
(so the false negatives increases by   (   +    )1 − )). Note that the sum    +    does not change
after error detection, as any true positive “detected” as being incorrect becomes a false negative, and
false negatives do not otherwise change from error detection. Therefore, the new recall is:
When this quantity is subtracted from the original recall (  ), we obtain:
   −   (1 − )(   +    )</p>
      <p>+   
=   (1 − ) (
=</p>
      <p>−   (1 − )(   +    )
  −    +   
   − (   −   (1 − )(   +    ))</p>
      <p>+   
=   (1 − )(   +    ))</p>
      <p>+   
   +    )
   +       +   
=   (1 − ) (  +    )
   +   
We note that    =      −    =    − ⋅   which gives us:
  (1 − ) (  +</p>
      <p>−    ⋅  
 (   +    )   (   +    )</p>
      <p>)
=   (1 − ) (  +   −   )</p>
      <p>= (1 − ) 
 
 
(28)
(29)
(30)
(31)
(32)
(33)
(34)
CLAIM 2: (1 − ) 
conditions in the rule 
 
  is a normalized polymatroid submodular function with respect to the set of
 . Note that 
is the number of samples that satisfy the body, while  
is
the number of samples that satisfy the body and head,   =   − 
 
  = (1 − 
=
=</p>
      <p>)</p>
      <p>1  
   
for</p>
      <p>statement of the theorem follows.</p>
      <p>A.3. Proof of Theorem 3
As 1   is a constant, we need to show the submodularity of  
which follows the same argument
as per Claim 4 of Theorem 1. Likewise,  
is monotonic (mirroring the argument of Claim 5
of Theorem 1) and normalized by the definition of   in the case where there are no conditions. The
For the application of error correcting rules, both precision and recall increase if and only if rule
confidence (  ) increases.</p>
      <p>Proof. CLAIM 1: Precision increases by −

 .</p>
      <p>The new precision is equal to the following:</p>
      <p>+
The improvement of the precision can be derived as follows.</p>
      <p>+ 
  + 
   + 
  + 
−   =
=
=
=
=
   + −
   + − 
 −
  +
  +
  +
−
  +




  −  

 −  
CLAIM 2: If count of samples satisfying both rule body and head (the numerator of confidence)
increases, then precision increases.</p>
      <p>Suppose BWOC the claim is not true. Then for some value of  
for which the improvement in
precision is greater than  
′ =   + 1</p>
      <p>. Note that, in this case, the number of samples satisfying the
body also increases by 1. First, we know that we can re-write the result of claim 1 as follows.

Therefore, using the result from Claim 1, the following relationship must hold.


 &gt; 
&gt;
  + 1 − 

This gives us a contradiction, as  (1 −   ) ≥ 0 and   ≤</p>
      <p>CLAIM 3: If the diference in precision increases, the number of samples satisfying both rule body and
By definition, the only way for this to occur is if 
increases and  
does not - as they can both
increase. If neither there is no change, and it is not possible for  
to increase
. Therefore the following must be true.

&lt;
However, this is clearly a contradiction the expression on the right is clearly smaller (the numerator is
smaller as   is positive, and the denominator is larger).</p>
      <p>CLAIM 4: Precision increases if and only if  increases.</p>
      <p>Follows directly from claims 1-3.</p>
      <p>CLAIM 5: When adding more samples that satisfy the body of the rule, confidence increases if and only
head must increase.
increase or only 
without 
if</p>
      <p>increases.
but not  
true.</p>
      <p>+ 
 + 
 &lt;  
 &lt;  
&lt;

 

 

2
&gt;</p>
      <p>1 &gt; 
 2 &gt;  1
1
2</p>
      <p>to increase alone. Therefore, BWOC, the following must hold
This is a contradiction as  ≥</p>
      <p>Going other way, suppose BWOC confidence increases but POS does not. We get:
However, by the statement, as we add more samples that satisfy the body of the rule, we must have

1 ≤</p>
      <p>2. Hence a cotnradiction.</p>
      <p>CLAIM 6: Recall increases if and only if</p>
      <p>increases.</p>
      <p>As we can write the new recall in this case simply as the following, the claim immediately follows.
CLAIM 7: Recall increases if and only if  increases.</p>
      <p>Proof of theorem.</p>
      <p>Follows directly from claims 5-6.</p>
      <p>Follows directly from claims 4 and 7.</p>
      <p>
        A.4. Overall Accuracy Results for Other Data Splits
Previous work such as [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] is known to have data leakage based on the split between training and test
primarily due to segments of a movement sequence existing in both training and test sets resulting
from ransom assignment to each. To address this data leakage issue, we examine our algorithms under
various conditions based on ordering and overlap. For ordering, we examine random (which can allow
previous behavior of the same agent in the training set, as in previous work) and sequential (which
      </p>
      <p>Random
LRCNa (ours) 0.747 0.751
LRCNa+EDCR (ours) 0.759 (+1.6%) 0.763 (+1.6%)
LRCN (prev. SOTA) 0.749 0.747
LRCN+EDCR (ours) 0.761 (+1.6%) 0.760 (+1.7%)
CNN 0.742 0.755
CNN+EDCR (ours) 0.743 (+0.1%) 0.755 (± 0%)</p>
      <p>No Overlap</p>
      <p>Sequential Random
(least leakage) (known leakage,
prev. studies)
0.971
0.971 (± 0%)
0.952
0.952 (± 0%)
0.851
0.866 (+1.8%)</p>
      <p>Segment Overlap</p>
      <p>Sequential</p>
    </sec>
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