Naive Bayes High Low Return Prediction Algorithm based on Jim Obreen's Post

This post is based on “How to Leverage the Pipeline to Conduct Machine Learning in the IDE” by Jim Obreen and presents a modification of Jim's notebook using previous returns as decision variables and a Gaussian Naive Bayes predictor of high and low return stocks after days to instead of Linear Regression, this algorithms is also based on the Analysis of a Naive Bayes High Low Return Predictor using Previous Returns Notebook

20
Backtest from to with initial capital
Total Returns
--
Alpha
--
Beta
--
Sharpe
--
Sortino
--
Max Drawdown
--
Benchmark Returns
--
Volatility
--
 Returns 1 Month 3 Month 6 Month 12 Month
 Alpha 1 Month 3 Month 6 Month 12 Month
 Beta 1 Month 3 Month 6 Month 12 Month
 Sharpe 1 Month 3 Month 6 Month 12 Month
 Sortino 1 Month 3 Month 6 Month 12 Month
 Volatility 1 Month 3 Month 6 Month 12 Month
 Max Drawdown 1 Month 3 Month 6 Month 12 Month
#########################################################################################
# We use a Gaussian Naive Bayes model to predict if a stock will have a high return
# or low return next Monday (num_holding_days = 5),  using as input decision variables
# the assets growthto yesterday from 2,3,,4,5,6,7,8,9 and 10 days before
# We use the code form post [“How to Leverage the Pipeline to Conduct Machine Learning in the IDE”]
# by Jim Obreen to preprocess teh data
#########################################################################################

##################################################
# Imports
##################################################

from __future__ import division
from collections import OrderedDict
import time

# Pipeline, Morningstar, and Quantopian Trading Functions
from quantopian.algorithm import attach_pipeline, pipeline_output, order_optimal_portfolio
from quantopian.pipeline import Pipeline, CustomFactor
from quantopian.pipeline.data import Fundamentals
from quantopian.pipeline.data.builtin import USEquityPricing
from quantopian.optimize import TargetWeights
from quantopian.pipeline.factors import Returns

# The basics
import pandas as pd
import numpy as np

# SKLearn :)
from sklearn.naive_bayes import GaussianNB

##################################################
# Globals
##################################################

num_holding_days = 5 # holding our stocks for five trading days.
days_for_fundamentals_analysis = 20
upper_percentile = 20
lower_percentile = 30

MAX_GROSS_EXPOSURE = 1.0
MAX_POSITION_CONCENTRATION = 0.05

##################################################
# Initialize
##################################################

def initialize(context):
""" Called once at the start of the algorithm. """

# Configure the setup
set_asset_restrictions(security_lists.restrict_leveraged_etfs)

# Schedule our function
schedule_function(rebalance, date_rules.week_start(), time_rules.market_open(minutes=1))

# Build the Pipeline
attach_pipeline(make_pipeline(), 'my_pipeline')

##################################################
# Pipeline-Related Code
##################################################

class Predictor(CustomFactor):
""" Defines our machine learning model. """

# The factors that we want to pass to the compute function. We use an ordered dict for clear labeling of our inputs.
factor_dict = OrderedDict([
('Asset_Growth_2d' , Returns(window_length=2)),
('Asset_Growth_3d' , Returns(window_length=3)),
('Asset_Growth_4d' , Returns(window_length=4)),
('Asset_Growth_5d' , Returns(window_length=5)),
('Asset_Growth_6d' , Returns(window_length=6)),
('Asset_Growth_7d' , Returns(window_length=7)),
('Asset_Growth_8d' , Returns(window_length=8)),
('Asset_Growth_9d' , Returns(window_length=9)),
('Asset_Growth_10d' , Returns(window_length=10)),
('Asset_Growth_15d' , Returns(window_length=15)),
('Asset_Growth_10d' , Returns(window_length=10)),
('Asset_Growth_20d' , Returns(window_length=20)),
('Return' , Returns(inputs=[USEquityPricing.open],window_length=5))
])

columns = factor_dict.keys()
inputs = factor_dict.values()

# Run it.
def compute(self, today, assets, out, *inputs):
""" Through trial and error, I determined that each item in the input array comes in with rows as days and securities as columns. Most recent data is at the "-1" index. Oldest is at 0.

!!Note!! In the below code, I'm making the somewhat peculiar choice  of "stacking" the data... you don't have to do that... it's just a design choice... in most cases you'll probably implement this without stacking the data.
"""

## Import Data and define y.
inputs = OrderedDict([(self.columns[i] , pd.DataFrame(inputs[i]).fillna(0,axis=1).fillna(0,axis=1)) for i in range(len(inputs))]) # bring in data with some null handling.
num_secs = len(inputs['Return'].columns)
y = inputs['Return'].shift(-num_holding_days)
y=y.dropna(axis=0,how='all')

for index, row in y.iterrows():

upper = np.nanpercentile(row, upper_percentile)
lower = np.nanpercentile(row, lower_percentile)
auxrow = np.zeros_like(row)

for i in range(0,len(row)):
if row[i] <= lower:
auxrow[i] = -1
elif row[i] >= upper:
auxrow[i] = 1

y.iloc[index] = auxrow

y=y.stack(dropna=False)

## Get rid of our y value as an input into our machine learning algorithm.
#del inputs['Return']

## Munge x and y
x = pd.concat([df.stack(dropna=False) for df in inputs.values()], axis=1).fillna(0)

## Run Model
model = GaussianNB()
model_x = x[:-num_secs*(num_holding_days)]
model.fit(model_x, y)

out[:] =  model.predict(x[-num_secs:])

def make_pipeline():

pipe = Pipeline(columns={'Model': Predictor(window_length=days_for_fundamentals_analysis, mask=universe)},screen = universe)

return pipe

##################################################
# Execution Functions
##################################################

def rebalance(context,data):
""" Execute orders according to our schedule_function() timing."""

# Timeit!
start_time = time.time()

## Run pipeline
pipeline_output_df = pipeline_output('my_pipeline').dropna(how='any')

todays_predictions = pipeline_output_df.Model

# Demean pipeline scores
target_weight_series = todays_predictions.sub(todays_predictions.mean())

# Reweight scores to prepare for portfolio ordering.
target_weight_series = target_weight_series/target_weight_series.abs().sum()

order_optimal_portfolio(objective=TargetWeights(target_weight_series),constraints=[])

# Print useful things. You could also track these with the "record" function.
print 'Full Rebalance Computed Seconds: '+'{0:.2f}'.format(time.time() - start_time)
print "Number of total securities trading: "+ str(len(target_weight_series[target_weight_series > 0]))
print "Leverage: " + str(context.account.leverage)
There was a runtime error.