What Is a Signal Line?
Signal lines are average lines used in technical indicators, especially oscillators. They generate buy and sell signals, 𒈔or they can suggest a change in a trend. They aಌre called signal lines because when another indicator or line crosses, them it sends a signal to execute a trade.
An indicator crossing a signal line can also signal that something potentially important is happening with the price of an asset. It could be that the price was trending, 澳洲幸运5开奖号码历史查询:pulled back, and is now starting to trend again, or it could signal that a new uptrend or downtrend is starti𝓡ng.
澳洲幸运5开奖号码历史查询:Signal lines are often moving ave𓆏rages of a technical indicator, such as the 澳洲幸运5开奖号码历史查询:moving average convergen💦ce-diverge♔nce (MACD) or 澳洲幸运5开奖号码历史查询:stochastic oscillator. The signal line is applied to the indicator to generate more trade signals th💟an would be available without the signal line.
A signal line is also commonly known as a "trigger line."
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Image by Sabrina Jiang © Investopedia 2021
Key Takeaways
- A signal line is a line that, when crossed by another indicator, signals that a trade should occur or that an important price change has happened.
- A signal line is not a technical indicator in and of itself.
- Signal lines may be used in different ways for different indicators.
- Typically an indicator crossing above the signal line is interpreted as bullish for the price, while crossing below the signal line it is bearish for the price.
Signal Line Formula
Because a signal line is not itself an indicator, ♔it will be calculated differently for each indicator in which it is used. The creator of꧂ an indicator will often generate a formula for the signal line when making the indicator. The signal line is part of the indicator.
Signal lines are usually simple calculations. For example, the signal line for the MACD is a nine-period 澳洲幸运5开奖号码历史查询:exponential moving average (EMA) of the MACD value.
The signal line for the stochastic oscillator is a three-period 澳洲幸运5开奖号码历史查询:simple moving average (SMA) of the stochas꧑tic (called %K in this🦹 case).
How to Create a Signal Line
To create a signal line:
- Find the formula for the signal line of the indicator you are using. This is typically an EMA or SMA of the indicator.
- Calculate the indicator or add it to a chart in 澳洲幸运5开奖号码历史查询:charting software.
- Calculate the EMA or SMA of the indicator.
- Alternatively, apply the applicable moving average to the indicator on the chart to create the signal line.
How to Use a Signal Line
Most signal lines are created by using a moving average of the indicator values. These moving averages are ⛎usually simple moving averages (SMAs) or exponential moving averages (EMAs).
Fast Fact
Signal lines can be applied to many different techᩚᩚᩚᩚᩚᩚᩚᩚᩚ𒀱ᩚᩚᩚnical indicators, but the moving average convergence-divergence (MACD) and stochastic ꦿoscillators are the two most popular.
Signal lines may also be used to indicate a change in the momentum of a trend. For example, if an indiꦗcator crosses above the signal line it indicates the price is starting to move up. If an indicator crosses below the signal line it indicates the price is starting to move down.
These signals are typically used in conjunction with other pieces of information. For example, if the price is visibly in a longer-term uptrend, a trader may consider only taking long trades on bullish crossovers. They may sell when there is a bearish crossover, but they wouldn't enter a short positiꩵon because that would go against the longer-term uptrend.
Other pieces of information that signal line crossovers are often used in conjunction with include forms of technical analysis, such as technical indicators, chart patterns, or 澳洲幸运5开奖号码历史查询:candlestick patterns that provide confirmation. As another example, traders may use 澳洲幸运5开奖号码历史查询:pivot points to identify potential turning points and then look to MACD crossovers for confirmation of a reversal.
Limitations of Signal Lines
Signal lines are usually just a moving average of an indicator. In this way, the signal line lags the movements of the indi𒅌cator. As the indicator reacts to price changes it moves quicker than the signal line and this generates a crossover.
While signal lines can produce good signals at times, which result in large trend changes and price moves, many crossovers will be 澳洲幸运5开奖号码历史查询:false signals. A false signal is when the indicator crosses the signal line but the price fails to move in the direction expected. The pri𝔉ce may also crisscross the signal line, resulting in multiple signals which lose the trader money if the trade signals are traded.
For these reasons, signal line crossovers are rarely used in isolation. Other forms of technical or 澳洲幸运5开奖号码历史查询:fundamental analysis a💎re used to confirm trade signals or rule out taking certain signal lin♑e trades.
What Is the Difference Between a Signal Line and a Moving Average?
In technical analysis, a 澳洲幸运5开奖号码历史查询:moving average is based on price or sometimes volume, such as the 200-day 🍰moving average of price. In most cases, a signal line is a moving average. However, it is called a signal line to indicate why it is used. This helps avoid confusion with the price-based moving averages. Signal lines are a moving average of an indicator calculation. They are used to generate trade signals for t𒀰hat indicator only.
What Are the 2 Types of Moving Average?
The two main types of moving averages are an exponential🌠 moving average (EMA) and a simple moving average (SMA). Both are calculated over a chosen time period. An SMA applies equal weight to all price changes during that time, while an EMA is more responsive to the most recent price changes.
Is a Signal Line a Leading or a Lagging Indicator?
A signal line is not a technical indicator itself, but a moving average of 澳洲幸运5开奖号码历史查询:a chosen indicator that is used to track important changes. The ꦚindicator it is used with may be leading or lagging. For example, a signal line is often used to track the moving average convergence/divergence (MACD), which is a lagging indicator.
The Bottom Line
In investing, a signal line marks the point when a trade should take place if it is crossed by another indicator (such as price price). It can also signal to investors that a significant change has happ𒐪ened. By itself, it is not a technical indicator, but ⛎it is often paired with other technical indicators.
Usually, if an indicator crosses above the signal line, it's considered bullish for the price; if the indicator crosses below, it's considered bearish. In general, signal lines are a moving average of the indicator they are paired with. This limits their utility, as they may lag the movement of the indicator. They are also prone to sending false signals. Because of this, signal lines should be paired with other types of technical analysis in trading and investing.