Average precision for classification. Calculate the Average Precision for all the classes.

top_k_accuracy_score(y_true, y_score, *, k=2, normalize=True, sample_weight=None, labels=None) [source] #. mAP is measured between 0 and 1. If this case is encountered for any class/label, the metric for that class/label will be set to 0 and the overall metric may therefore Jan 18, 2023 · The next step has a bit more complexity. Feb 23, 2022 · 1. This is macro-averaged F1-score. I have been setting the scoring parameter to scoring='average_precision' when cross validating on my training set using sklearn's cross_val_score. Micoaverage precision, recall, f1 and accuracy are all equal for cases in which every instance must be classified into one (and only one) class. 95 + 0. Jun 2, 2022 · Would average=None or average="macro" be appropriate for your case? E. Compute label ranking average precision score for multilabel data [1]. 91; macro-average: precision = 0. For example, when Precision is 100% and Recall is 0%, the F1-score will be 0%, not 50%. In the average_precision_score function, the mandatory parameters are as follows: y_true: True binary labels in binary label indicators. 50. 93 + 0. Let's first see F1-Score for binary classification. 8 (80%) was set for both IoU and the classification confidence score to compute the average precision (AP) score for each class, calculated as the weighted mean of precisions at each threshold. But you can use the following snippet to get accuracy, sensitivity, and specificity. Precision is referred to as the positive predictive value. Besides the traditional object detection techniques, advanced deep learning models like R-CNN and YOLO can achieve impressive detection over different types of May 21, 2016 · 7. sum(0) F1c = (2*precision*recall) / (precision+recall) # per-class F1 score micro-averaged F1 score For some use cases individual class F1 scores are all you need, but we can also compute a micro-averaged F1 score to summarize the quality across all classes with a single number. If I randomly change the order of the training samples, I get the same classification accuracy but a very different meanAP. In my last article we looked in detail at the confusion matrix, model accuracy The weighted mean precision is calculated by taking the average of precision of every class. 78%. Apr 5, 2020 · Weighted average between precision and recall. F1 score is a measure of a model’s accuracy, taking into account both precision and recall. bool in the right way. Precision and recall are defined for a single binary classification problem, they cannot be used directly for either multi-class or multi-label classification. Where \ (\text {TP}\) and \ (\text {FP}\) represent the number of true positives and false positives respectively. Simulation Setup Dec 2, 2020 · Why mean Average Precision. Apr 21, 2020 · The mathematics isn’t tough here. One of the metrics used in evaluating classification models is F1 score. Precision is a metric that quantifies the number of correct positive predictions made. diag(C) # true positives precision = TP/C. 22; Class Mango F1-score Feb 26, 2021 · Average precision (AP) and many other related evaluation indices have been employed ubiquitously in classification tasks for a long time. Our computed values match those generated by sklearn. 10 until v0. Precision: the ability of a classification model to return only the data points in a class. mAP@0. 5 series, but only a small change for gpt-4 and text-bison-002, albeit with a different precision-recall By computing a precision and recall at every position in the ranked sequence of documents, one can plot a precision-recall curve, plotting precision () as a function of recall . Precision shows how often an ML model is correct when predicting the target class. 0000000 0. Macro Average. Simply the average precision, recall and f1 score between classes. In computer vision, object detection is the problem of locating one or more objects in an image. Top-5 accuracy was popularized by the ImageNet challenge. mAP is equal to the average of the Average Precision metric across all classes in a model. Through various investigations and examples, I was able to confirm that the values of precision, recall, and f-1 score are the same. 5 means, while for average precision, it’s a little bit more tricky to see what the different orders of magnitude mean, or the different scales mean, but it can be more fine-grained measure. The mean average precision@K measures the average precision@K averaged over all queries (for the entire dataset). The numerators are the same, and every FN for one class is another classes's FP, which makes the Jun 9, 2020 · The mean Average Precision or mAP score is calculated by taking the mean AP over all classes and/or overall IoU thresholds, depending on different detection challenges that exist. Precision is a ratio of the number of true positives divided by the sum of the true positives and false positives. Apparently you're using macro-average and your Nov 12, 2023 · mAP50: Mean average precision calculated at an intersection over union (IoU) threshold of 0. 75 + 0. Like precision_u =8/ (8+10+1)=8/19=0. 3. Jan 25, 2012 · The answer is that you have to compute precision and recall for each class, then average them together. It is defined as the average of recall obtained on each class. For example, if 60% of the classes in an animal dataset To evaluate top-5 accuracy, the classifier must provide relative likelihoods for each class. Nov 5, 2023 · I have been studying multi-class classification metrics. As we have seen from figure “Precision, Recall and F1-score for Each Class”, Class Apple F1-score = 0. In pattern recognition, information retrieval, object detection and classification (machine learning), precision and recall are performance metrics that apply to data retrieved from a collection, corpus or sample space . A simple way to see this is by looking at the formulas precision=TP/ (TP+FP) and recall=TP/ (TP+FN). (I'm not sure I fully grasp the intent of mdmc_average in your example, so this might not make sense in your case. Precision. The F1 score (aka F-measure) is a popular metric for evaluating the performance of a classification model. example based on your model. 40; Class Orange F1-score = 0. This metric Apr 28, 2020 · For unbalanced classes, I would suggest to go with Weighted F1-Score or Average AUC/Weighted AUC. 0). When training an object detection model you want to quantify and compare different models and tell which model performs better than the other. In the process, I discovered that in the case of the parameter average='micro', accuracy, precision, recall, and the f-1 score are all the same. assume TP of Apr 14, 2021 · The classification of imbalanced data has presented a significant challenge for most well-known classification algorithms that were often designed for data with relatively balanced class distributions. Similarly to ROC AUC score you can calculate the Area Under the Precision-Recall Curve to get one number that describes model performance. Accuracy. 95. sklearn. Micro averaging computes a global average F1 score by counting the sums of the True Positives (TP), False Negatives (FN), and False Positives (FP). Nov 5, 2023 · Mean average precision (mAP) is a metric used to evaluate the performance of object detection models. Average precision computes the average value of p ( r ) {\displaystyle p(r)} over the interval from r = 0 {\displaystyle r=0} to r = 1 {\displaystyle r=1} : [7] To evaluate object detection models like R-CNN and YOLO, the mean average precision (mAP) is used. It describes how good a model is at predicting the positive class. We can see that the model has skill, achieving a ROC AUC above 0. The Average Precision@K or AP@K is the sum of precision@K where the item at the kₜₕ rank is relevant ( rel(k)) divided by the total number of relevant items (r) in the top K recommendations (figure 6). 1)). This is done by calculating the AP across a set of IoU thresholds for each class n and then May 11, 2019 · In order to extend the precision-recall curve and average precision to multi-class or multi-label classification, it is necessary to binarize the output. Top-k Accuracy classification score. 55 Ra = 10/17 = 0. So the mAP is averaged over all object classes. 77 + 0. The mAP hence is the Mean of all the Average Precision values across all your classes as measured above. The classifier will only get a high F-score if both precision and recall are high. Mar 8, 2023 · Recall: the ability of a classification model to identify all data points in a relevant class. Useful when dealing with unbalanced samples. Micro and Macro AP were computed for lesion detection and to determine classification confidence [34]. Here are the steps to compute the precision-recall curve for class A: Compute the average precision (AP) score for binary tasks. Dec 30, 2023 · Micro-averaging and macro-averaging scoring metrics is used for evaluating models trained for multi-class classification problems. Aug 1, 2020 · Precision for Imbalanced Classification. We first sum the respective TP, FP, and FN values across all classes and then sklearn. We know Precision = TP/(TP+FP), so for Pa true positive will be Actual A predicted as A, i. a coin toss) has an average precision equal to the percentage of positives in the class, e. However, they have defects and can hardly provide both overall evaluations and individual evaluations. Figure 6. Precision, therefore, calculates the accuracy for the minority class. Our average precision over all classes Jan 18, 2024 · Mean average precision for object detection (i. confusion matrix of multi-class classification. It's of course technically possible to calculate macro (or micro) average performance with only two classes, but there's no need for it. Here is an example from my research: This is a classification report I got in one of my classifiers. The weighted average is higher for this model because the place where precision fell down was for class 1, but it’s underrepresented in this dataset (only 1/5), so accounted for less in the weighted average. It provides an overall performance measure for an object detection algorithm Compute Mean Average Precision. Micro-averaging precision scores is sum of true positive for individual classes divided by sum Jul 14, 2020 · A random classifier (e. metrics. hence your macro-avg is 51. In your case, the macro average precision, recall, and F1-score are all around 0. 50 to 0. You can use mAP to compare both different models on the same task and different versions of the same model. PR AUC score | Average precision. It is calculated as the ratio of correctly predicted positive examples divided by the total number of positive examples that were predicted. The first step in computing the mAP is to find the degree of overlap between the ground truth and the predicted bounding boxes. 55, f1-score = 0. Average Precision (AP) and mean Average Precision (mAP) are the most popular metrics used to evaluate object detection models, such as Faster R_CNN, Mask R-CNN, and YOLO, among others. Just a few things to consider: Summing over any row values gives us Precision for that class. Precision; Recall; Confusion Matrix; Classification Accuracy. Therefore, using the numbers for TPs and FPs seen above, we can calculate precision as follows: (3) So, for this particular example, the precision of the classifier is . Macro-averaging scores are arithmetic mean of individual classes’ score in relation to precision, recall and f1-score. Precision measures the number […] This repo contains the official implementation of HAPPIER: Hierarchical Average Precision Training for Pertinent Image Retrieval (ECCV'22). Say this would be my results: y_true = [0, 1, 2, 1, 1] y_pred Jul 2, 2019 · It’s actually quite simple! But first, let’s start with a quick recap of precision and recall for binary classification. It is especially prevalent in certain application domains with great need for machine learning and better Aug 26, 2020 · AP, mAP, and AP50, among other metrics, are explained with an example. Find Mean Average Precision (mAP) by averaging APs. If I want to measure the Precision for each class, I will set the class_id for each class and did not set the top_k I am only getting values of the precision for the first and last classes, and the other classes are showing (0. Recall shows whether an ML model can find all objects of the target class . Macro average doesn't take class Oct 26, 2020 · The macro average precision is 0. 50 (50%) with a ground truth object. 95: In contrast Aug 10, 2017 · 2 facts: As stated in other answers, Tensorflow built-in metrics precision and recall don't support multi-class (the doc says will be cast to bool). in your case macro-avg = (precision of class 0 + precision of class 1)/2. Moving forward we recommend using these versions. 7. 833. ) – To evaluate object detection models like R-CNN and YOLO, the mean average precision (mAP) is used. We first sum the respective TP, FP, and FN values across all classes and then Jan 4, 2022 · Image by author and Freepik. I'm no expert, but this is what I have determined based on the following sources: Jan 26, 2018 · The precision at each recall level r is interpolated by taking the maximum precision measured for a method for which the corresponding recall exceeds r. Mean Average Precision@K. 88 + 0. The same metrics have also been used to evaluate submissions in competitions like COCO and Metrics and scoring: quantifying the quality of predictions — scikit-learn 1. g. The micro-average will adequately capture this class imbalance, and bring the overall precision average down to 0. mAP50-95: The average of the mean average precision calculated at varying IoU thresholds, ranging from 0. It is calculated by finding the Average Precision (AP) for each class and then the average over several classes. class_id: id of a particular class. A go to metric is the mean Average Precision (mAP). Basically we use the maximum precision for a given recall value. However with this code I get some strange results. There are ways of getting one-versus-all scores by using precision_at_k by specifying the class_id, or by simply casting your labels and predictions to tf. 10 an 'binary_*', 'multiclass_*', 'multilabel_*' version now exist of each classification metric. Aug 14, 2023 · mAP, or mean Average Precision, is the average of the AP values calculated for multiple object classes or categories. Compute Precision. Classification accuracy is the simplest evaluation metric. As you can see in the last column of the resultant matrix in the Results Workspace, class precision for 'pred. 9090909 0. In practice, we have to strike a balance between whole and individual performances to satisfy diverse demands. 2 of true positives and by the time we hit 0. Weighted Avg: The weighted average gives a weighted average of precision, recall, and F1-score, where each class's contribution is weighted by its support (the number of Feb 24, 2020 · For the ranking based losses, I think both average precision and ROC AUC are pretty good choices, ROC AUC, I like it because I know what 0. 42 is the precision for class Jun 3, 2016 · TP = np. yes' is 77. In PASCAL VOC2007 challenge, AP for one object class is calculated for an IoU threshold of 0. The metric is only proper defined when \ (\text {TP} + \text {FP} \neq 0\). 5, and the weighted average is 0. This F1 score is known as the macro-average F1 score. It is usually higher than top-1 Sep 15, 2023 · mAP@0. Jan 15, 2024 · Applying logprob classification achieves a massive increase in F1 of ~16 pp for the gpt-3. 80), and class 3 (0. Not only is the correct classification but also the correct localization decisive for the quality of your model. Consider running the example a few times and compare the average outcome. When these are sorted, a classification is considered correct if the correct classification falls anywhere within the top 5 predictions made by the network. Feb 4, 2020 · Note: Your results may vary given the stochastic nature of the algorithm or evaluation procedure, or differences in numerical precision. Understanding F1 Score When building a machine learning model, it is crucial to evaluate its performance to ensure it is accurate and reliable. Micro-averaging is found by dividing the sum of the diagonal Jun 19, 2022 · The calculated value of 0. Micro Average. 64 tallies with the weighted-averaged F1 score in our classification report. Classification accuracy is a fundamental metric for evaluating the performance of a classification model, providing a quick snapshot of how well the model is performing in terms of correct predictions. 95, recall = 0. Sep 10, 2018 · 2. 89), the weighted average will be calculated by multiplying each score by the number of occurrences of each class and dividing by the total number of samples. To calculate the AP, you will need to follow these steps: 1. From v0. These aggregates can be computed for recall and f1-score as well. ROC curves typically feature true positive rate (TPR) on the Y axis, and false positive rate (FPR) on the X axis. Simulation Setup TL;DR. It's a measure of the model's accuracy considering only the "easy" detections. Calculate the Average Precision for all the classes. Normally one specifies which of the two classes is the positive one (usually the minority class), and then regular precision, recall and F-score can be used. (There’s also Part II: the F1-score, but I recommend you start with Part I). (1/2 + 1 + 1) / 3 = 5/6 = 0. The F1 score can be interpreted as a harmonic mean of the precision and recall, where an F1 score reaches its best value at 1 and worst score at 0. Putting all this together, we end up with our classification report. The mAP compares the ground-truth bounding box to the detected box and returns a score. 4. 123 (more in line with the precision of the dominating class B (0. def class_matric(confusion_matrix, class_id): """. A perfect classifier has an average precision of 1. Best score is 1. sum(1) recall = TP/C. 91, f1-score = 0. According to the definition of the average precision (AP) score in here, the AP is calculated based on the precision and increment in recall across thresholds. In binary classification we usually have two classes, often called Positive and Negative, and we try to predict the class for each sample. Overlap Criterion. 4. 95724. The Classification Report. May 11, 2024 · All the metrics we explored and discussed above (accuracy, precision, recall, macro average, weighted average, F1-score, AUC-ROC score, ROC curve) can be applied to any type of classification problem. 32. Convert the prediction scores into class labels. Thanks for the detailed answer, it is really helpful. So. Sep 13, 2021 · What is Average Precision@K ? AP@K is the sum of precision@K for different values of K divided by the total number of relevant items in the top K results. Jan 4, 2021 · The Geometric Mean or G-Mean is a metric for imbalanced classification that, if optimized, will seek a balance between the sensitivity and the specificity. Where TP is the number of true positives, FN is the Compute average precision (AP) from prediction scores. The precision is intuitively the ability of the This example describes the use of the Receiver Operating Characteristic (ROC) metric to evaluate the quality of multiclass classifiers. May 6, 2020 · Mean Average Precision (mAP) is used to measure the performance of computer vision models. One curve can be drawn per label, but one can also draw a precision-recall curve by considering each element of the label indicator matrix as a binary prediction (micro-averaging). To define the term, the Average Precision metric (or just AP) is the weighted mean of Precision scores achieved at each PR curve threshold, with the increase in Recall from the previous threshold used as the Apr 21, 2024 · Let’s dive into the features of the classification report. So the MAP is averaged over all object classes. 59 Jun 19, 2022 · The calculated value of 0. Jul 14, 2020 · A random classifier (e. The most common overlap criterion is the Intersection over Union (IoU) that takes the predicted bounding box Evaluating Deep Learning Models: The Confusion Matrix, Accuracy, Precision, and Recall. 91, recall = 0. Jun 9, 2021 · If 3 (precision scores) for 3 classes are: Class 1 (0. Localization pinpoints an object’s position using (e. micro: this is the same as accuracy. AP summarizes a precision-recall curve as the weighted mean of precisions achieved at each threshold, with the increase in recall from the previous threshold used as the weight: AP = ∑ n ( R n − R n − 1) P n. I just have one small question regarding the last point. 727. It is defined as the number of correct predictions divided by the total number of predictions multiplied by 100. Accuracy shows how often a classification ML model is correct overall . total labels with lower score. 8750000 If you wanted to grab the precision for a particular class, you could do: Aug 26, 2017 · precision_score(y_test, y_pred, average=None) will return the precision scores for each class, while . The sum of true positives and true negatives divided by the total number of samples. The best value is 1 and the worst value Feb 20, 2015 · This function uses the vl_pr function from vlfeat to compute the average precision for a single class. Visualizing Recall and Precision. 92) / 10 = 0. Compute the precision. There are 3 different APIs for evaluating the quality of a model’s predictions: Estimator score method: Estimators have a score method providing a default evaluation criterion Jun 12, 2024 · For the positive class precision is starting to fall as soon as we are recalling 0. Commonly there is a majority and a minority Note. To this end, we propose a new index for Nov 30, 2023 · It's the average of these metrics across all classes, giving each class equal weight. 18. The relative contribution of precision and recall to the F1 score are equal. Jul 3, 2024 · Classification Accuracy; Logarithmic loss; Area under Curve; F1 score. 11. Oct 28, 2020 · The goal of this classification problem is to optimize for precision at all possible thresholds and rank test data by the likelihood of being in the positive class. balanced_accuracy_score(y_true, y_pred, *, sample_weight=None, adjusted=False) [source] #. As input to forward and update the metric accepts the following input: preds ( Tensor ): A float tensor of shape (N, C To calculate the mean average precision, we need to compute the precision-recall curve for each class, and then average the area under each curve. What is the Average Precision score? Like the Area under the Precision-Recall curve (AUC-PR) metric, Average Precision is a way to summarize the PR curve into a single value. Precision(num_classes=5, multiclass=False, average="macro", mdmc_average="samplewise"). 0. 90 + 0. It calculates metrics for each class individually and then takes unweighted mean of the measures. Mar 18, 2024 · The most popular metric to evaluate an object detector is mean Average Precision (mAP). 8, it decreases to around 0. You will learn how mAP evolved over time from PASCAL VOC to MS COCO. Oct 10, 2023 · These measures are also useful in applied machine learning for evaluating binary classification models. Mar 23, 2014 · Now we calculate three values for Precision and Recall each and call them Pa, Pb and Pc; and similarly Ra, Rb, Rc. , 10, rest of the two cells in that column, whether it is B or C, make False Positive. Jun 15, 2022 · So, the macro average precision for this model is: precision = (0. It is calculated by averaging the precision-recall curves for each object class. e. Jun 5, 2020 · The mean average precision or MAP score is calculated by taking the mean AP over all classes and/or overall IoU thresholds, depending on different detection challenges that exist. And then I average the results over all classes. AP@K formula (image by author). Macro F1. . while weighed avg is the total number TP(true positive of all classes)/total number of objects in all classes. One approach would be to test the model with each threshold returned from the call roc_auc_score () and select the threshold with the largest G-Mean value. 5. However one can use micro-average or macro-average precision (or recall), this is the standard way to evaluate with multiple classes. - elias-ramzi/HAPPIER May 27, 2024 · 1. , bounding box coordinates), and classification identifies it (whether it’s a dog or a cat). For example: In the PASCAL VOC2007 challenge, AP for one object class is calculated for an IoU threshold of 0. Jan 12, 2021 · In multi-label classification, the classifier assigns multiple labels (classes) to a single input. Statistical Jan 31, 2024 · The mean average precision (mAP) is the averaged APs across all classes at different IoU thresholds. Same for recall. Compute the balanced accuracy. In the case of multi-class classification, we adopt averaging methods for F1 score calculation, resulting in a set of different average scores (macro, weighted, micro) in the classification report. 5, in this case achieving a mean score of 0. if you classes A, B, and C, then your precision is: (precision(A) + precision(B) + precision(C)) / 3. Metrics and scoring: quantifying the quality of predictions #. E. 853. ROC curves Jan 4, 2020 · macro-avg is mean average macro-avg is mean average precision/recall/F1 of all classes. The higher the score, the more accurate the model is in its detections. Consider the class balance and costs of different errors when choosing the suitable metric. This means that the top left corner of the plot is the “ideal” point - a FPR of zero, and a Sep 29, 2016 · No, There is no built-in way for getting accuracy scores for each class separately. The balanced accuracy in binary and multiclass classification problems to deal with imbalanced datasets. no' is 60% and class precision for 'pred. Precision quantifies the fraction of true positives out of all detected objects, while recall measures the fraction of true positives out of all actual objects in Nov 9, 2020 · micro-average: precision = 0. F-Measure = (2 * Precision * Recall) / (Precision + Recall) The F-Measure is a popular metric for imbalanced classification. The accuracy metric works great if the target variable classes in the data are approximately balanced. The score is the average over each ground truth label assigned to each sample of the ratio of true vs. The AP score summarizes a precision-recall curve as an weighted mean of precisions at each threshold, with the difference in recall from the previous threshold as weight: \ [AP = \sum {n} (R_n - R_ {n-1}) P_n\] where \ (P_n, R_n\) is the respective precision and recall at threshold Apr 30, 2021 · Recall = TruePositive / (TruePositive + FalseNegative) Precision and recall can be combined into a single score that seeks to balance both concerns, called the F-score or the F-measure. So when it is important for you to predict well the small class and predicting the big class is relatively easy, I'm suggesting to use only f1-score of the small class as main metric, or using Precision-Recall AUC(PR-AUC) as main metric. precision_score(y_test, y_pred, average='micro') will return the total ratio of tp/(tp + fp) The pos_label argument will be ignored if you choose another average option than binary. Note that the multilabel case isn’t covered here. Generate the prediction scores. Calculate the 4 attributes of the confusion matrix. May 23, 2018 · I have to calculate precision and recall for a university project to measure the quality of the classification output (with sklearn). precision_score(y_true, y_pred, *, labels=None, pos_label=1, average='binary', sample_weight=None, zero_division='warn') [source] #. 68 + 0. It gives a comprehensive view of the model's Oct 7, 2017 · Precision for each class (assuming the predictions are on the rows and the true outcomes are on the columns) can be computed with: (precision <- diag(mat) / rowSums(mat)) # setosa versicolor virginica # 1. Nevertheless skewed class distribution is a common feature in real world problems. 70; Assuming we don't know anything else than the selected performance measure, this classifier: performs almost perfectly according to the performance of the majority class A, performs very well according to micro-average, May 29, 2020 · Precision = Recall = Micro F1 = Accuracy. 1 documentation. y_score: Target scores, can either be Nov 20, 2023 · Remember that precision is the number of True Positives divided by the number of True Positives plus False Positives. where P n and R n are the precision and recall at the nth threshold [1 Nov 4, 2020 · 4. For computational reasons, it may sometimes be more convenient to compute class averages and then macro-average them. This base metric will still work as it did prior to v0. Pa = 10/18 = 0. 50: This metric assesses how well a model can locate objects with a moderate Intersection over Union (IoU) overlap of at least 0. F1 score: a single metric that combines recall and precision using the harmonic mean. , localization and classification tasks) is one of the commonly used evaluation metrics in computer vision (CV). The precision is the ratio tp / (tp + fp) where tp is the number of true positives and fp the number of false positives. 0. 80 + 0. The formula for the F1 score is: F1 = 2 ∗ TP 2 ∗ TP + FP + FN. Aug 9, 2022 · Calculate Average Precision (AP) using the PASCAL VOC 11-point interpolation method. 2. Precision (also called positive predictive value) is the fraction of relevant instances among the retrieved instances. This metric computes the number of times where the correct label is among the top k labels predicted (ranked by predicted scores). Jul 20, 2021 · Classification: Based on some inputs, F1 score is the weighted average of precision and recall. Aug 1, 2023 · The threshold value of ≥ 0. 85), class 2 (0. Weighted average precision considers the number of samples of each label as well. When to Use What (Recap) Nov 1, 2021 · Averaging this, we get our samples average for precision. Please feel free to calculate the macro average recall and macro average f1 score for the model in the same way. 12 if there are 12% positive examples in the class. The F1-score gives a larger weight to lower numbers. For more details about average precision, see this post. yj ml eb ii fg hw vk ts sc rs