
The strategy trades NYSE, AMEX, and NYSE MKT stocks by leveraging shared analyst coverage, going long on high connected-stock returns and short on low, with monthly value-weighted rebalancing.
ASSET CLASS: stocks | REGION: United States | FREQUENCY:
Monthly | MARKET: equities | KEYWORD: Momentum
I. STRATEGY IN A NUTSHELL
This strategy trades NYSE, AMEX, and NYSE MKT stocks with analyst coverage, excluding stocks under $5. Stocks linked via shared analyst coverage are ranked monthly by the connected-stock portfolio return (CS RET). The strategy goes long on the quintile with the highest CS RET and short on the lowest. Portfolios are value-weighted and rebalanced monthly, leveraging shared analyst coverage for return predictability.
II. ECONOMIC RATIONALE
Investor information-processing limits drive connected-stock relationships. Analyst co-covered peers better explain cross-sectional return and fundamental variation than traditional industry peers. Using these linkages improves predictability of firm-specific returns, providing a robust framework for forecasting and understanding return dynamics.
III. SOURCE PAPER
Shared Analyst Coverage and Cross-Asset Momentum Effects [Click to Open PDF]
Ali, Usman, Pacific Investment Management Company (PIMCO)
<Abstract>
Identifying firm connections by shared analyst coverage, we find that a connected-firm (CF) momentum factor generates a monthly alpha of 1.68% (t = 9.67). In spanning regressions, the alphas of industry, geographic, customer, customer/supplier industry, single- to multi-segment, and technology momentum factors are insignificant/negative after controlling for CF momentum. Similar results hold in cross-sectional regressions and in developed international markets. Sell-side analysts incorporate news about linked firms sluggishly. These effects are stronger for complex and indirect linkages. Consistent with limited investor attention, these results indicate that momentum spillover effects are a unified phenomenon that is captured by shared analyst coverage.


IV. BACKTEST PERFORMANCE
| Annualised Return | 11.22% |
| Volatility | 19.28% |
| Beta | 0.133 |
| Sharpe Ratio | 0.56 |
| Sortino Ratio | -0.066 |
| Maximum Drawdown | N/A |
| Win Rate | 47% |
V. FULL PYTHON CODE
from AlgorithmImports import *
from dateutil.relativedelta import relativedelta
from pandas.core.series import Series
from pandas.core.frame import dataframe
class ConnectedStocksMomentumPortfolio(QCAlgorithm):
def Initialize(self):
self.SetStartDate(2010, 1, 1)
self.SetCash(100_000)
self.weight: Dict[Symbol, float] = {}
self.quantile: int = 5
self.price_data: Dict[Symbol, RollingWindow] = {}
self.m_period: int = 12
self.d_period: int = 21
self.universe_selection_period: int = 1
self.recent_estimate_date_by_analyst: Dict[str, Dict[str, datetime.date]] = {}
market: Symbol = self.AddEquity('SPY', Resolution.Daily).Symbol
self.required_exchanges: List[str] = ['NYS', 'ASE', 'NAS']
self.already_subscribed: List[Symbol] = []
self.leverage: int = 10
self.min_share_price: float = 5.
self.fundamental_count: int = 500
self.fundamental_sorting_key = lambda x: x.DollarVolume
self.selection_flag: bool = False
self.rebalance_flag: bool = False
self.UniverseSettings.Resolution = Resolution.Daily
self.AddUniverse(self.FundamentalSelectionFunction)
self.Settings.MinimumOrderMarginPortfolioPercentage = 0.
self.Schedule.On(self.DateRules.MonthStart(market), self.TimeRules.AfterMarketOpen(market), self.Selection)
def OnSecuritiesChanged(self, changes: SecurityChanges) -> None:
for security in changes.AddedSecurities:
security.SetFeeModel(CustomFeeModel())
security.SetLeverage(self.leverage)
def FundamentalSelectionFunction(self, fundamental: List[Fundamental]) -> List[Symbol]:
# update the rolling window every day
for stock in fundamental:
symbol: Symbol = stock.Symbol
# store daily price
if symbol in self.price_data:
self.price_data[symbol.Value].Add(stock.AdjustedPrice)
if not self.selection_flag:
return Universe.Unchanged
# select new universe once a period
if self.Time.month % self.universe_selection_period != 0:
self.rebalance_flag = True
return Universe.Unchanged
selected: List[Fundamental] = [x for x in fundamental if x.HasFundamentalData
and x.Market == 'usa'
and x.MarketCap != 0
and x.Price >= self.min_share_price
and x.SecurityReference.ExchangeId in self.required_exchanges
]
if len(selected) > self.fundamental_count:
selected = [x for x in sorted(selected, key=self.fundamental_sorting_key, reverse=True)[:self.fundamental_count]]
min_date: datetime.date = self.Time.date() - relativedelta(months=self.m_period)
cf_ret: Dict[Fundamental, float] = {}
for stock in selected:
symbol: Symbol = stock.Symbol
i_ticker: str = stock.Symbol.Value
# subscribe Estimize data
if symbol not in self.already_subscribed:
self.AddData(EstimizeEstimate, symbol)
self.already_subscribed.append(symbol)
# warmup price rolling windows
if symbol.Value not in self.price_data:
self.price_data[symbol.Value] = RollingWindow[float](self.d_period)
history: dataframe = self.History(symbol, self.d_period, Resolution.Daily)
if history.empty:
self.Log(f"Not enough data for {symbol} yet.")
continue
closes: Series = history.loc[symbol].close
for time, close in closes.items():
self.price_data[symbol.Value].Add(close)
if self.price_data[symbol.Value].IsReady:
# nij indexed by j
n_ij: Dict[str, int] = {}
for analyst, ticker_estimate_dates in self.recent_estimate_date_by_analyst.items():
# i was covered by analyst
if i_ticker in ticker_estimate_dates:
# check period of the last coverage
if ticker_estimate_dates[i_ticker] >= min_date:
for j_ticker, date_list in ticker_estimate_dates.items():
if j_ticker != i_ticker:
# price data for j is ready
if j_ticker in self.price_data and self.price_data[j_ticker].IsReady:
# check period of the last coverage
if ticker_estimate_dates[j_ticker] >= min_date:
# found connected stocks covered by an analyst
ticker_pair:tuple[str, str] = (i_ticker, j_ticker)
# increment of analysts who cover both tickers i and j
if j_ticker not in n_ij:
n_ij[j_ticker] = 0
n_ij[j_ticker] += 1
# calculate CF RET
N:int = len(n_ij)
if N != 0:
cf_ret[stock] = (1 / sum(list(n_ij.values())) * sum([nij * (self.price_data[j_t][0] / self.price_data[j_t][self.d_period - 1] - 1) for j_t, nij in n_ij.items()]))
self.rebalance_flag = True
if len(cf_ret) >= self.quantile:
# CF RET sorting
sorted_by_cf_ret: List = sorted(cf_ret.items(), key = lambda x:x[1], reverse=True)
quantile: int = int(len(sorted_by_cf_ret) / self.quantile)
long: List[Fundamental] = [x[0] for x in sorted_by_cf_ret[:quantile]]
short: List[Fundamental] = [x[0] for x in sorted_by_cf_ret[-quantile:]]
# market cap weighting
for i, portfolio in enumerate([long, short]):
mc_sum:float = sum(map(lambda x: x.MarketCap, portfolio))
for stock in portfolio:
self.weight[stock.Symbol] = ((-1) ** i) * stock.MarketCap / mc_sum
return list(self.weight.keys())
def OnData(self, slice: Slice) -> None:
# store latest EPS Estimize estimate
estimize = slice.Get(EstimizeEstimate)
for symbol, value in estimize.items():
ticker: str = symbol.Value
if value.AnalystId not in self.recent_estimate_date_by_analyst:
self.recent_estimate_date_by_analyst[value.AnalystId] = {}
if ticker not in self.recent_estimate_date_by_analyst[value.AnalystId]:
self.recent_estimate_date_by_analyst[value.AnalystId][ticker] = datetime.min
self.recent_estimate_date_by_analyst[value.AnalystId][ticker] = value.CreatedAt.date()
if not self.rebalance_flag:
return
if not self.selection_flag:
return
self.selection_flag = False
self.rebalance_flag = False
# trade execution
portfolio: List[PortfolioTarget] = [PortfolioTarget(symbol, w) for symbol, w in self.weight.items() if symbol in slice and slice[symbol]]
self.SetHoldings(portfolio, True)
self.weight.clear()
def Selection(self) -> None:
self.selection_flag = True
# Custom fee model.
class CustomFeeModel(FeeModel):
def GetOrderFee(self, parameters):
fee = parameters.Security.Price * parameters.Order.AbsoluteQuantity * 0.00005
return OrderFee(CashAmount(fee, "USD"))