10.3 Sentiment Measured from Market Data

Once sentiment is defined, CMT Level I asks where you measure it. This unit is sentiment from market data: series that are produced by trading, not by a journalist or a poll. Independent OpenExamPrep material for these CMT Level I topics stays on the named tools — VIX, futures open interest, options volume and open interest (put/call), the three Commitments of Traders (COT) groups, insider activity, and short interest — and on what each one says about the crowd. Later Advanced-domain work returns to volatility as a statistical object. Here VIX is a mood.

A later Classical unit already taught open interest as sponsorship (new money versus covering). Keep that. This section adds the sentiment question: at this price extreme, is the crowd fully aboard, forced out, or still adding risk?

VIX as a sentiment measure

The Cboe Volatility Index (VIX) is Cboe's measure of market expectations of near-term volatility conveyed by S&P 500 Index (SPX) option prices. In ordinary technician language it is about 30-day expected volatility of the S&P 500. Cboe and practitioners have long treated it as a barometer of investor sentiment and market volatility. Two empirical regularities matter at Level I:

1. VIX typically moves inversely to the S&P 500. When the index sells off, demand for SPX options (especially puts) lifts implied volatility and VIX rises. When the index grinds higher, implied vol is offered and VIX falls. A long-volatility overlay has historically been a rough hedge to long equities; that is a relationship, not a promise that every VIX up-tick pays.
2. High VIX is fear; low VIX is complacency. Spikes into the 30s and far beyond (2008 and March 2020 both printed crisis-level VIX) mark forced hedging and panic put buying. Sleepy prints in the low teens mark a crowd that is not paying up for insurance. Neither print is a clock. A VIX of 12 can persist through a long advance (timing challenge from 10.2). A VIX of 35 can print before the final low.

Use VIX as sentiment context:

• Rising VIX with a falling index: fear is increasing with the decline — often the healthy (if unpleasant) pattern of a sponsored downswing, and at a climax a contrary-bullish warning.
• Falling VIX with a rising index: complacency / comfort with the advance — confirming in a trend, contrary-bearish only if other books are also one-sided.
• VIX falling while the index is still making lower lows: fear is fading into weakness — a mixed, often dangerous tape.
• VIX rising while the index makes new highs: the crowd is paying up for insurance into strength — not automatic distribution, but not sleepwalking either.

Do not invent an official Cboe "buy at 12, sell at 30" rule. Illustrative bands below are context, not Association cut scores. A quiet year can spend most of its time in the teens and still spike into the 30s without those numbers becoming laws. Chapter 16 will go deeper on implied versus historical vol; this unit's job is the fear gauge.

Futures open interest as sentiment

Open interest (OI) is the stock of outstanding futures (or options) contracts that have not been closed, exercised, or delivered. As sentiment, ask what a change in OI says about whether the crowd is adding or exiting at the current price.

Sentiment extras that the volume chapter does not emphasize:

• Record OI at a price high can mean the crowd is fully aboard — a positioning extreme, especially if commercials are leaning the other way.
• Collapsing OI after a spike can mean the crowded book got out, which often is the turning process.
• OI is exchange-reported and lagged relative to the tick. It is a stock, not a day's volume.

Worked numbers: crude rallies from $70 to $90 while combined OI rises from 1.8 million to 2.3 million contracts. New risk entered. That is confirming bullish sentiment in the futures book. If price then tags $92 on a drop in OI back toward 2.0 million, the last lift looks like covering, not a new crowd arriving — a sentiment warning even if the dollar print is a new high.

Options volume and open interest as sentiment (put/call)

Options produce two sentiment meters from the same rights to buy or sell:

• Volume put/call = put contracts traded ÷ call contracts traded (over a session or a window).
• Open-interest put/call = put OI ÷ call OI (the stock of outstanding puts versus calls).

High put/call (more puts relative to calls) reads as fear or heavy hedging. At extremes, technicians commonly treat it as contrary-bullish: the crowd that wanted downside insurance already paid for it. Low put/call (calls dominate) reads as complacent or speculative bullishness; at extremes, contrary-bearish.

Three traps:

1. Equity versus index versus total. Cboe equity put/call is closer to speculative demand in single names. Index put/call runs higher because portfolio managers buy index puts as hedges even in ordinary weeks. Mixing the two series, or treating a structurally higher index ratio as a panic print, is a common error.
2. Hedging versus speculation. A pension buying SPX puts is not the same crowd as a retail trader buying puts on a meme name. Volume spikes in cheap out-of-the-money puts are more emotional than a systematic collar.
3. Not a same-day timer. A put/call spike can mark the crash day or the day before the crash day. Pair it with price.

Illustrative (not official) context: many equity put/call histories spend a lot of time below 1.0. Prints pushing toward 1.0+ are the ones technicians circle as fear, not the everyday 0.6 handle. Do not memorize a single threshold as if Cboe published a pass mark.

Three primary groups in the Commitments of Traders report

The U.S. Commodity Futures Trading Commission (CFTC) Commitments of Traders (COT) report, in the legacy breakdown, splits futures (and combined futures-and-options) open interest into:

CFTC classification is based on the trader's predominant business purpose (Form 40), not on CFTC staff knowing why each lot was placed. A commercial's futures book includes that firm's positions in that commodity even when a given lot is not a textbook hedge. Disaggregated reports (producer/merchant, swap dealer, managed money, other reportable) exist; Level I still wants the three primary legacy groups.

Classic reading, with the required grain of salt:

• Commercials often sell into strength (producer hedges inventory) and buy into weakness (consumers lock in supply). That can look like smart-money contrary positioning at extremes.
• Noncommercials often add in the trend's direction (confirming) and are max positioned near turns (contrary).
• Nonreportables are the book most often wrong at extremes in the old lore.

Caveat you should be able to write: a grain commercial who is net short at harvest may be hedging a full silo, not forecasting a crash because of a chart. Always read COT with the price trend and the physical season. COT is as-of Tuesday, released Friday — a lag, not a tick.

Insider activity as sentiment

Insider activity is legal trading by officers, directors, and large beneficial owners in their own company's shares, reported on SEC Form 4 (and related forms). For a technician it is a strong-form information overlay: people with books-and-records access are putting money to work, or taking it off.

Level I reading rules:

• Clustered open-market buying is the stronger signal. Several insiders buying in size, with cash, after a decline, is sentiment that the people closest to the firm see asymmetric upside — or at least do not see imminent disaster.
• Routine selling is weaker. Executives sell for taxes, diversification, option-expiry mechanics, and houses. A sale is not automatically a forecast of a crash.
• Aggregate insider indexes (net buyers versus sellers across the market) are used as a market-level sentiment series: heavy net buying after a washout is contrary-bullish context; heavy selling into a melt-up is a warning, not a trigger.
• Filings have a short legal lag (Form 4 is due within two business days of the transaction under current U.S. rules) but they are still not the same as the tick.

Insider sentiment does not replace price. Insiders can be early by months. Treat a buy cluster as informed positioning, then ask whether the tape agrees.

Short interest as sentiment

Short interest is the number of shares that have been sold short and not yet covered. Two standard scalings:

• Short interest ratio (days to cover) = short interest ÷ average daily volume.
• Short interest as a percent of float (or of shares outstanding, depending on the vendor).

Worked numbers: 20 million shares short, average volume 2 million shares/day → 10 days to cover. That is a crowded short relative to a name with 2 days to cover. Crowding has two readings at once:

1. The crowd is bearish (they borrowed stock to sell it). At extremes that can be contrary-bullish if covering would have to chase a rising tape.
2. The same crowding is squeeze fuel. A lift in price forces buys to return shares. High short interest is therefore not a clean "price must fall" forecast.

Reports have historically been lagged snapshots (exchange/FINRA cycles), not a live locate tape. Like COT, do not treat a two-week-old short-interest print as this morning's book. Pair days-to-cover with price and volume: a short-interest extreme plus a high-volume upside reversal is a different story from a short-interest extreme plus another lower low.

Putting the market-data toolbox on one page

None of these series abolishes the four challenges in 10.2. Use clusters, know the as-of date, and wait for price.

Key Takeaways

• VIX: near-term SPX implied vol; fear when high, complacency when low; typically inverse to the S&P 500
• Futures OI: new risk versus liquidation at the current price
• Put/call volume and OI: fear versus complacency; equity versus index series are not interchangeable
• COT: commercials (hedgers), noncommercials (large specs), nonreportables (small specs)
• Insiders: cluster buying is the stronger tell; short interest is days-to-cover and two-sided at extremes