FEAT: Initialize benktander_demo.py.

Author: genedan

faslr/demos/methods/benktander/benktander_demo.py

@@ -0,0 +1,55 @@
+import chainladder as cl
+import sys
+
+from faslr.demos.sample_db import set_sample_db
+
+from faslr.methods.benktander import (
+    BenktanderWidget
+)
+
+import pandas as pd
+
+from faslr.utilities import (
+    load_sample,
+    table_from_tri,
+    auto_bi_olep
+)
+
+from PyQt6.QtWidgets import (
+    QApplication
+)
+
+set_sample_db()
+
+app = QApplication(sys.argv)
+
+averages = pd.DataFrame(
+    data=[
+        [True, "7-year Straight", "Straight", "7"],
+        [False, "7-year Excl. High/Low", "Medial", '7'],
+        [False, "3-year Straight", "Straight",  "3"],
+        [False, "5-year Straight", "Straight", "5"],
+    ],
+    columns=["Selected", "Label", "Type", "Number of Years"]
+)
+
+
+
+triangle = load_sample('xyz')
+reported = triangle['Reported Claims']
+paid = triangle['Paid Claims']
+
+reported_ult = cl.TailConstant(tail=1).fit_transform(cl.Development(n_periods=2, average='volume').fit_transform(reported))
+reported_ult = cl.Chainladder().fit(reported_ult)
+
+paid_ult = cl.TailConstant(tail=1.010,decay=1).fit_transform(cl.Development(n_periods=2, average='volume').fit_transform(paid))
+paid_ult = cl.Chainladder().fit(paid_ult)
+
+widget = BenktanderWidget(
+    triangles=[reported_ult, paid_ult],
+    premium=auto_bi_olep,
+    averages=averages
+)
+widget.show()
+
+app.exec()