diff --git a/basicts/metrics/__init__.py b/basicts/metrics/__init__.py
index c06c1b51..4d88ba8e 100644
--- a/basicts/metrics/__init__.py
+++ b/basicts/metrics/__init__.py
@@ -3,13 +3,19 @@
 from .mse import masked_mse
 from .rmse import masked_rmse
 from .wape import masked_wape
+from .smape import masked_smape
+from .r_square import masked_r2
+from .corr import masked_corr
 
 ALL_METRICS = {
             'MAE': masked_mae,
             'MSE': masked_mse,
             'RMSE': masked_rmse,
             'MAPE': masked_mape,
-            'WAPE': masked_wape
+            'WAPE': masked_wape,
+            'SMAPE': masked_smape,
+            'R2': masked_r2,
+            'CORR': masked_corr
             }
 
 __all__ = [
@@ -18,5 +24,8 @@
     'masked_rmse',
     'masked_mape',
     'masked_wape',
+    'masked_smape',
+    'masked_r2',
+    'masked_corr',
     'ALL_METRICS'
-]
+]
\ No newline at end of file
diff --git a/basicts/metrics/corr.py b/basicts/metrics/corr.py
new file mode 100644
index 00000000..95cbdcdd
--- /dev/null
+++ b/basicts/metrics/corr.py
@@ -0,0 +1,50 @@
+import numpy as np
+import torch
+
+
+def masked_corr(prediction: torch.Tensor, target: torch.Tensor, null_val: float = np.nan) -> torch.Tensor:
+    """
+    Calculate the Masked Pearson Correlation Coefficient between the predicted and target values,
+    while ignoring the entries in the target tensor that match the specified null value.
+
+    This function is particularly useful for scenarios where the dataset contains missing or irrelevant
+    values (denoted by `null_val`) that should not contribute to the loss calculation. It effectively
+    masks these values to ensure they do not skew the error metrics.
+
+    Args:
+        prediction (torch.Tensor): The predicted values as a tensor.
+        target (torch.Tensor): The ground truth values as a tensor with the same shape as `prediction`.
+        null_val (float, optional): The value considered as null or missing in the `target` tensor. 
+            Default is `np.nan`. The function will mask all `NaN` values in the target.
+
+    Returns:
+        torch.Tensor: A scalar tensor representing the masked mean absolute error.
+
+    """
+
+    if np.isnan(null_val):
+        mask = ~torch.isnan(target)
+    else:
+        eps = 5e-5
+        mask = ~torch.isclose(target, torch.tensor(null_val).expand_as(target).to(target.device), atol=eps, rtol=0.0)
+
+    mask = mask.float()
+    mask /= torch.mean(mask)  # Normalize mask to avoid bias in the loss due to the number of valid entries
+    mask = torch.nan_to_num(mask)  # Replace any NaNs in the mask with zero
+
+    prediction_mean = torch.mean(prediction, dim=1, keepdim=True)
+    target_mean = torch.mean(target, dim=1, keepdim=True)
+
+    # 计算偏差 (X - mean_X) 和 (Y - mean_Y)
+    prediction_dev = prediction - prediction_mean
+    target_dev = target - target_mean
+
+    # 计算皮尔逊相关系数
+    numerator = torch.sum(prediction_dev * target_dev, dim=1, keepdim=True)  # 分子
+    denominator = torch.sqrt(torch.sum(prediction_dev ** 2, dim=1, keepdim=True) * torch.sum(target_dev ** 2, dim=1, keepdim=True))  # 分母
+    loss = numerator / denominator
+
+    loss = loss * mask  # Apply the mask to the loss
+    loss = torch.nan_to_num(loss)  # Replace any NaNs in the loss with zero
+
+    return torch.mean(loss)
\ No newline at end of file
diff --git a/basicts/metrics/r_square.py b/basicts/metrics/r_square.py
new file mode 100644
index 00000000..5034440f
--- /dev/null
+++ b/basicts/metrics/r_square.py
@@ -0,0 +1,44 @@
+import numpy as np
+import torch
+
+
+def masked_r2(prediction: torch.Tensor, target: torch.Tensor, null_val: float = np.nan) -> torch.Tensor:
+    """
+    Calculate the Masked R square between the predicted and target values,
+    while ignoring the entries in the target tensor that match the specified null value.
+
+    This function is particularly useful for scenarios where the dataset contains missing or irrelevant
+    values (denoted by `null_val`) that should not contribute to the loss calculation. It effectively
+    masks these values to ensure they do not skew the error metrics.
+
+    Args:
+        prediction (torch.Tensor): The predicted values as a tensor.
+        target (torch.Tensor): The ground truth values as a tensor with the same shape as `prediction`.
+        null_val (float, optional): The value considered as null or missing in the `target` tensor. 
+            Default is `np.nan`. The function will mask all `NaN` values in the target.
+
+    Returns:
+        torch.Tensor: A scalar tensor representing the masked mean absolute error.
+
+    """
+
+    eps = 5e-5
+    if np.isnan(null_val):
+        mask = ~torch.isnan(target)
+    else:
+        mask = ~torch.isclose(target, torch.tensor(null_val).expand_as(target).to(target.device), atol=eps, rtol=0.0)
+
+    mask = mask.float()
+    prediction, target = prediction * mask, target * mask
+
+    prediction = torch.nan_to_num(prediction)
+    target = torch.nan_to_num(target)
+
+    ss_res = torch.sum(torch.pow((target - prediction), 2), dim=1)  # 残差平方和
+    ss_tot = torch.sum(torch.pow(target - torch.mean(target, dim=1, keepdim=True), 2), dim=1)  # 总平方和
+    
+    # 计算 R^2
+    loss = 1 - (ss_res / (ss_tot + eps))
+    
+    loss = torch.nan_to_num(loss)  # Replace any NaNs in the loss with zero
+    return torch.mean(loss)
diff --git a/basicts/metrics/smape.py b/basicts/metrics/smape.py
new file mode 100644
index 00000000..48e41666
--- /dev/null
+++ b/basicts/metrics/smape.py
@@ -0,0 +1,53 @@
+import torch
+import numpy as np
+
+def masked_smape(prediction: torch.Tensor, target: torch.Tensor, null_val: float = np.nan) -> torch.Tensor:
+    """
+    Calculate the Masked Symmetric Mean Absolute Percentage Error (SMAPE) between predicted and target values,
+    ignoring entries that are either zero or match the specified null value in the target tensor.
+
+    This function is particularly useful for time series or regression tasks where the target values may 
+    contain zeros or missing values, which could otherwise distort the error calculation. The function 
+    applies a mask to ensure these entries do not affect the resulting MAPE.
+
+    Args:
+        prediction (torch.Tensor): The predicted values as a tensor.
+        target (torch.Tensor): The ground truth values as a tensor with the same shape as `prediction`.
+        null_val (float, optional): The value considered as null or missing in the `target` tensor. 
+            Defaults to `np.nan`. The function will mask all `NaN` values in the target.
+
+    Returns:
+        torch.Tensor: A scalar tensor representing the masked mean absolute percentage error.
+
+    Details:
+        - The function creates two masks:
+          1. `zero_mask`: This mask excludes entries in the `target` tensor that are close to zero, 
+             since division by zero or near-zero values would result in extremely large or undefined errors.
+          2. `null_mask`: This mask excludes entries in the `target` tensor that match the specified `null_val`. 
+             If `null_val` is `np.nan`, the mask will exclude `NaN` values using `torch.isnan`.
+        
+        - The final mask is the intersection of `zero_mask` and `null_mask`, ensuring that only valid, non-zero,
+          and non-null values contribute to the MAPE calculation.
+    """
+
+    # mask to exclude zero values in the target
+    zero_mask = ~torch.isclose(target, torch.tensor(0.0).to(target.device), atol=5e-5)
+
+    # mask to exclude null values in the target
+    if np.isnan(null_val):
+        null_mask = ~torch.isnan(target)
+    else:
+        eps = 5e-5
+        null_mask = ~torch.isclose(target, torch.tensor(null_val).to(target.device), atol=eps)
+
+    # combine zero and null masks
+    mask = (zero_mask & null_mask).float()
+
+    mask /= torch.mean(mask)
+    mask = torch.nan_to_num(mask)
+
+    loss = torch.abs(prediction - target) / ((prediction.abs() + target.abs()) / 2)
+    loss *= mask
+    loss = torch.nan_to_num(loss)
+
+    return torch.mean(loss)