def per_model_mean(runs_df):
    """Computes the grouped mean and std by model type
    Args: 
        runs_df (pd.Dataframe): A list of all the runs
    Returns:
        A tuple of pandas Dataframes that represent the mean and std of each model
    """

    overall = runs_df.drop(columns=['SEED', 'ID']).groupby(['TYPE', 'MODEL', 'DATASET_ID'], 
        as_index=False).mean()
    collected = overall.drop(columns=['DATASET_ID']).groupby(['TYPE', 'MODEL'])
    return collected.mean()