T13 · Peer comparison

Co-trading with other members

Does the member trade the same stock in the same direction as other members at the same time more than chance predicts?

What would look suspicious

Shared nonpublic information spreads through networks and shows up as clustered trades.

Statistic

Share of trades with another member trading the same issuer the same way within five business days; excess over the circular-shift null

c_m=\frac1N\sum_i\mathbf 1\{\exists k\ne m,\ i'\in k: j(i')=j(i),\ d_{i'}=d_i,\ |t_{i'}-t_i|\le5\}

Inference

Circular-shift permutation of the member's trade dates; signed CAR of co-traded trades

Decision rule

Fits if co-trading is in excess and co-traded trades earn significantly positive signed returns. Open question if co-trading is in excess. Does not fit if co-trading is at or below its null mean.

Inputs

all members' tradesdaily returns (optional)

Limitations

Public news makes many members trade the same stock on the same day; excess co-trading is a pattern, not a channel.

Full derivation and algorithm: technical methodology (PDF), section T13.

Results across members

Fits patternOpen questionDoes not fitNot assessedScreening signal

0 fits · 12 open question · 131 do not fit · 103 not assessed

Distribution of member estimates (143 members)

0.0%62.5%

Highest estimates

0Estimate

Katie Boyd Britt62.5%

John Fetterman60.0%

Daniel Meuser57.7%

Morgan McGarvey53.8%

Cleo Fields48.8%

Ed Case47.4%

John J. McGuire III45.5%

Michael A. Rulli45.0%

Kelly Morrison42.9%

Adam Smith38.9%

Eleanor Holmes Norton38.5%

Lloyd Smucker35.5%

Members flagged by this test

Member	Reading	Estimate	Holm p	Summary
John Boozman Sen. · R-AR	Open question	15.5%	1.000	16% of trades had another member trading the same stock the same way within a week (chance alone: 11%).
Robert P. Bresnahan, Jr. Rep. · R-PA-8	Open question	31.6%	1.000	32% of trades had another member trading the same stock the same way within a week (chance alone: 23%).
Gilbert Ray Cisneros, Jr. Rep. · D-CA-31	Open question	13.0%	1.000	13% of trades had another member trading the same stock the same way within a week (chance alone: 8%).
Lloyd Doggett Rep. · D-TX-37	Open question	23.9%	1.000	24% of trades had another member trading the same stock the same way within a week (chance alone: 16%).
Lois Frankel Rep. · D-FL-22	Open question	7.0%	1.000	7% of trades had another member trading the same stock the same way within a week (chance alone: 4%).
Josh Gottheimer Rep. · D-NJ-5	Open question	18.9%	1.000	19% of trades had another member trading the same stock the same way within a week (chance alone: 14%).
Jonathan L. Jackson Rep. · D-IL-1	Open question	23.9%	1.000	24% of trades had another member trading the same stock the same way within a week (chance alone: 18%).
Daniel Meuser Rep. · R-PA-9	Open question	57.7%	1.000	58% of trades had another member trading the same stock the same way within a week (chance alone: 35%).
Kelly Morrison Rep. · D-MN-3	Open question	42.9%	1.000	43% of trades had another member trading the same stock the same way within a week (chance alone: 24%).
Dan Newhouse Rep. · R-WA-4	Open question	28.1%	1.000	28% of trades had another member trading the same stock the same way within a week (chance alone: 19%).
Gary C. Peters Sen. · D-MI	Open question	14.9%	1.000	15% of trades had another member trading the same stock the same way within a week (chance alone: 7%).
Jefferson Shreve Rep. · R-IN-6	Open question	25.7%	1.000	26% of trades had another member trading the same stock the same way within a week (chance alone: 9%).