# Linear Regression Analysis: Definition, How It Works, Assumptions, Limitations and When to Use

Linear regression analysis is a statistical method used to model linear relationships between variables. It estimates numerical values based on continuous input data by minimizing the difference between observed data points and a fitted regression line. This line serves to predict future values of the dependent variable using new independent variable values.

For accurate linear regression, certain assumptions must be met. Firstly, there should be a linear relationship between predictors and the response variable, with consistent change across predictor values. Residuals, or prediction errors, should be randomly distributed around a mean of zero without discernible patterns. Additionally, residuals must be independent of each other, and there should be no multicollinearity between predictors. Outliers should be minimal to prevent skewing the distribution, and residuals should follow a normal bell curve.

However, linear regression has limitations. It’s limited to simple linear models and cannot capture complex nonlinear relationships. Overfitting may occur with numerous independent variables without proper regularization. Moreover, it cannot directly model categorical predictors, only continuous numeric values, and may be influenced by confounding variables if not appropriately controlled.

## What Is Linear Regression Analysis?

Linear regression analysis is a statistical technique used to establish models of linear relationships between dependent and independent variables. It involves fitting a straight line through data points to minimize the distances between observed data and the line. The aim is to determine model parameters that best predict the value of a response variable based on one or more predictor variables. In financial markets, traders and investors utilize linear regression analysis to forecast price levels and make informed decisions by examining the relationship between price (dependent variable) and time (independent variable).

The linear regression line is represented as Y = a + bX, where Y is the response variable, X is the predictor variable, b is the slope, and a is the intercept. The slope indicates how Y changes for every one-unit change in X, while the intercept is the value of Y when X is zero.

Linear regression relies on several key assumptions. It assumes a linear relationship between predictors and the response variable, with residuals averaging zero and having a constant spread. The data points should be independent, with minimal overlap among predictors, and should not contain significant outliers. Additionally, the residuals should follow a normal distribution.

When these assumptions are met, linear regression analysis estimates the direction and magnitude of linear relationships present in the data. It is commonly used for prediction, forecasting, and assessing variable impacts across various fields such as finance, science, social science, and medicine to identify trends.

To construct a linear regression model, data is examined for linearity and assumption verification. Once confirmed, the line is fitted using least squares estimation to minimize residuals. The model’s performance is evaluated using metrics like R-squared, mean squared error, and p-values, with statistical tests validating the overall fit and individual predictors. The final model makes predictions based on the provided independent variables.

## How Does Linear Regression Analysis Work?

Linear regression analysis operates by modeling the relationship between a dependent variable and one or more independent variables as a linear function. The primary objective is to establish a linear regression equation that minimizes the disparity between the fitted line and the actual data points. This equation enables the estimation of the dependent variable’s value based on the independent variables.

The standard linear regression equation is represented as Y = a + bX, where Y denotes the dependent or response variable being predicted, and X signifies the independent or predictor variables utilized for prediction. The coefficient b represents the slope of the regression line, indicating the change in Y for each unit change in X. Meanwhile, the coefficient a corresponds to the y-intercept, denoting the value of Y when X is zero.

Linear regression employs ordinary least squares estimation to determine the regression line’s optimal values for the intercept and slope coefficients, minimizing the sum of squared residuals. Residuals represent the vertical distance between each data point and the regression line. By minimizing these residuals, the line is positioned as close as possible to all data points.

The resulting regression equation is utilized to make predictions by inputting values for the independent variables. Additionally, the regression output provides crucial statistics such as R-squared and p-values for evaluating model fit.

Before employing linear regression, analysts must ensure that certain assumptions are met. These include a linear relationship between the dependent and independent variables, zero mean and constant variance of residuals, independence of residuals, and a normal distribution without outliers.

If assumptions are violated, analysts undertake corrective actions such as data transformation, outlier removal, and regularization. They estimate linear regression coefficients using simple matrix calculations, typically implementing them through statistical software. The resulting model and its estimates remain valid within the data range used for training the model, necessitating regular monitoring, tuning, and retraining to maintain predictive accuracy over time.

### How Does Linear Regression Analysis Generate Predictions Easily?

Linear regression analysis simplifies the generation of predictions for the dependent variable by providing a straightforward mathematical equation derived from the fitted regression line. This equation encapsulates the relationship between the dependent variable (Y) and each independent variable (X1, X2, etc), allowing for easy prediction without the need for complex analysis each time.

The regression equation, typically represented as Y = b0 + b1X1 + b2X2 + … + bn*Xn, where b0 is the intercept and b1…bn are the regression coefficients for each independent variable, facilitates quick prediction. Each coefficient represents the change in Y for a one unit change in the corresponding X variable, enabling the assessment of each independent variable’s impact on the dependent variable and the generation of predictions for any combination of X values.

Linear regression models can handle nonlinear trends by transforming variables, such as taking the log of an independent variable to make the relationship linear. Categorical independent variables are incorporated through indicator or dummy variables, allowing different intercepts or slopes for different groups, with coefficients directly used for prediction.

With the regression equation and coefficients in hand, generating predictions is a simple process of multiplying values for each independent variable by their respective coefficients, summing up the results along with the intercept, and obtaining the predicted dependent variable value. Linear regression functions are built into various software packages and programming languages, automating the prediction process by providing new X values.

Prediction intervals are calculated around individual predictions to quantify uncertainty, with wider intervals indicating greater uncertainty. As long as linear regression assumptions like linearity and normality are met, the predictions are reliable, although violations may necessitate data transforms. Overall, the linear regression equation, coupled with estimated coefficients, offers a straightforward and efficient means of generating predicted values for the dependent variable, incorporating learned relationships from historical data without the need for additional analysis.

### How Is Linear Regression Analysis Used in Predicting Stock Market Trends and Patterns?

Linear regression serves as a vital tool in financial analysis and stock market prediction, allowing analysts to model the relationship between stock prices and various influencing factors. Here are nine key ways linear regression models facilitate the prediction of stock market trends and patterns.

Firstly, analysts may develop simple linear regression models with a stock’s price as the dependent variable and time as the independent variable to capture the overall trend in the stock’s price over a historical period.

Secondly, regressing a stock price on a market benchmark like the S&P 500 indexes its price movements to broader market trends, aiding in predicting the stock’s behavior based on forecasted movements in the overall market.

Additionally, analysts can add fundamentals such as sales, revenue, and earnings metrics as independent variables to relate a stock’s valuation to the company’s financial performance, thereby driving stock price predictions based on earnings forecasts.

Moreover, macro factors like interest rates, inflation, GDP growth, and unemployment can also be incorporated as drivers of stock prices, allowing predictions for how stock prices will respond to changes in economic conditions.

Furthermore, traders can utilize technical trading indicators like moving average crossovers, relative strength, and trading volumes to identify predictive price movements and guide forecasts.

Regressing a group of stocks against each other helps identify how they move together based on common sector or industry exposures, predicting different types of candlestick patterns.

Time series regressions like ARIMA models incorporate serial correlation in prices and lagged values of prices to forecast future price activity, capturing the time-oriented nature of stock data.

Moreover, regression coefficients quantify the exact relationships between independent variables and stock prices, aiding in understanding how various factors drive prices.

Lastly, predictive ability is evaluated by testing models out-of-sample to prevent overfitting and indicate how well relationships will hold up for future prediction.

### What Are the Assumptions of Linear Regression Analysis in Stock Market Forecasting?

Linear regression analysis, frequently used in stock market forecasting, relies on several key assumptions to ensure the validity and reliability of predictions. Here are the main assumptions:

Linear Relationship: There should be a straight-line relationship between the dependent variable (e.g., stock price) and independent variables (factors used for prediction). Nonlinear relationships require transformations.

Constant Variance of Residuals (Homoscedasticity): The variance of residuals should remain constant across all values of independent variables to avoid distorting relationships and significance tests.

Independence of Residuals: Residuals should be independent and random. Correlated residuals over time can narrow confidence intervals.

Normal Distribution of Residuals: Residuals should follow a normal bell curve distribution to ensure the validity of statistical inferences.

No Perfect Multicollinearity: Independent variables should not exhibit perfect collinearity, as it can cause estimation problems.

Correct Specification: The model should be properly specified with the appropriate functional form and relevant variables included.

No Measurement Error: Independent variables should be accurately measured to avoid inconsistent and biased estimates.

Appropriate Use of Available Data: Sample data should be representative of the population and cover the desired forecast period and target market adequately.

Coefficient Stability: The relationships quantified by the model should remain stable over the forecasting period.

Model Fit: The linear regression model should adequately explain variation in stock returns or prices, as measured by metrics like R-squared.

Prediction Intervals: Prediction intervals should be calculated around projected values to quantify the range of probable values and incorporate model uncertainty.

Out-of-Sample Testing: The model should be validated on an out-of-sample dataset to assess its predictive accuracy.

Domain Knowledge Use: Modeled relationships should align with practical domain knowledge of the stock market.

Simplicity: The model should strike a balance between simplicity and complexity to ensure reliable forecasting.

Regular Re-estimation: Models should be regularly re-estimated using the most recent data to reflect the current market conditions.

Quantitative Validation: Predictive ability should be quantitatively assessed using error metrics and directional accuracy metrics.

Economic Significance: Modeled relationships should make economic sense in terms of direction and magnitude.

Cautious Interpretation: Forecasts should be interpreted cautiously, recognizing that they are estimates subject to uncertainty.

Ensuring these assumptions are met is crucial to avoid generating misleading or inaccurate forecasts using linear regression models in stock market forecasting.

### What Are the Limitations of Linear Regression Analysis in Stock Market Forecasting?

Linear regression analysis, while valuable, has several limitations that hinder its effectiveness in predicting stock market behavior. It’s important to recognize these limitations for accurate application and realistic expectations:

Nonlinear Relationships: Linear regression struggles to capture complex nonlinear relationships inherent in stock market dynamics, necessitating the use of nonlinear modeling techniques.

Correlation Not Causation: Linear regression can only quantify correlations and cannot establish causation, limiting its predictive power if correlations break down.

Data Mining and Overfitting: Fitting numerous models and selecting the best historical fit often leads to overfitting, resulting in models that fail to generalize to new data.

Spurious Correlations: Some correlations found in sample data occur by chance and lack meaningful explanatory relationships, posing challenges in distinguishing them from persistent relationships.

Model Instability: Key relationships affecting stock prices change over time, rendering models estimated on historical data outdated and requiring periodic re-estimation.

Data Errors: Input data errors and noise influence model coefficients and distort predictions, necessitating identification and cleaning of anomalous data.

Omitted Variables: Excluding relevant variables from the model leads to inaccurate coefficients and distorted effects, making it difficult to capture all explanatory factors.

Confounding Variables: Omitted important explanatory variables that happen to be correlated with included variables complicate isolating the true drivers of stock prices.

Normality Assumption: Violating the assumption of normality in stock returns affects the validity of model inference and significance testing, sometimes requiring transformations.

Complex Interactions: Linear models struggle to capture complex multivariate interactions between variables prevalent in stock markets.

Unstructured Data: Linear regression cannot directly incorporate qualitative, unstructured data containing predictive information like news or investor sentiment.

Few Independent Observations: Time series data violates the assumption of independent observations, distorting model fitting and statistical tests.

Rare Events: Historical data-based modeling has limitations during rare events such as financial crashes, requiring expert human judgment.

False Precision: Linear models imply precision in forecasts that may not be warranted, necessitating the use of prediction intervals to quantify uncertainty.

Differences Across Stocks: Relationships vary across stocks, making it challenging to develop generalizable models applicable to diverse stocks.

Survivorship Bias: Models estimated on existing stock data may suffer from survivorship bias, skewing the modeling.

Alternative Data Needs: Linear regression relies solely on quantitative data inputs, ignoring valuable signals from alternative data sources.

Model Degradation: Model performance degrades over time as markets evolve, necessitating mechanisms to detect when a model is no longer effective.

Understanding these limitations helps practitioners use linear regression more effectively alongside domain expertise, human judgment, and robustness testing.

## When to Use Linear Regression?

Linear regression is a valuable tool in stock market analysis, particularly when used under the following circumstances:

Linear regression excels at quantifying historical linear relationships between stock prices/returns and potential driver variables like financial metrics, macro factors, technical indicators etc. The regression coefficients estimate the magnitude and direction of each variable’s relationship with the stock price/return, controlling for other factors. This reveals which variables have been most important historically. Statistical tests assess the significance of the overall model and individual predictors. R-squared evaluates overall fit. This understanding of historical correlations and variable importance can guide trading strategies and investment decisions.

The linear model is sometimes used to forecast expected returns based on current values of the predictor variables. The regression equation plugged with the latest input data generates predicted expected returns going forward. This works best when the true relationships are linear and the key drivers exhibit some persistence over time. Limitations arise when relationships are nonlinear or change substantially over time.

Regressing stock prices on market indexes models how closely the stock follows the overall market. This indexes the stock’s price to the benchmark. Industry and sector-based multi-stock models can identify groups of stocks that tend to move together and lead/lag each other. Macroeconomic models relate the stock market to the underlying economic conditions.

Fundamental stock valuation models relate prices to financial metrics like revenues, earnings, profit margins to quantify the underlying business value. Cross-sectional models estimate the typical relationships across a sample of stocks. Time series models focus on company-specific historical relationships.

The residuals from a linear model reveal when actual returns deviate significantly from predicted returns. Unusually large residuals indicate potential mis-pricing anomalies worth investigating. This aids active trading strategies.

Linear models provide a statistical framework to test classic investment theories like CAPM, Fama-French, and other factor models. The significance and explanatory power of theoretical risk factors are sometimes evaluated empirically.

However, linear regression has limitations in stock market analysis. Relationships are often nonlinear due to thresholds and saturation effects. Structural changes over time like regime shifts can reduce model reliability. Expert human judgment is still crucial to supplement pure data-driven models. Causality cannot be definitively established with correlations alone.

### How Does Linear Regression Analysis Help Portfolio Optimization and Risk Management?

Linear regression analysis plays a crucial role in portfolio optimization and risk management in the following ways:

Regression models quantify the historical risk and return characteristics of each asset class based on historical data. This provides inputs for mean-variance portfolio optimization models to determine optimal asset allocation mixes. Factors like volatility, skew, tail risks, and drawdowns can be modeled for downside risk assessment.

Correlations between asset classes can be modeled using regression to determine diversification benefits. Identifying low correlation pairs allows combining them into portfolios to improve the risk-return tradeoff. Regression also models lead-lag relationships between asset classes.

For a given portfolio, regressing individual stock returns on factors like market returns estimates each stock’s market beta. Stocks with higher betas are assigned smaller portfolio weights to manage overall portfolio risk exposure. Weights are also scaled lower for stocks with higher idiosyncratic volatility based on regression models.

Regressing asset returns on macroeconomic indicators models how return patterns change across economic regimes like expansion vs recession. This allows tilting portfolios proactively towards assets poised to perform well in an impending regime.

Regression models estimate the fair value for each asset based on fundamental drivers. Observing large residuals reveals assets trading significantly above or below fair value, identifying potential buying or selling opportunities. Momentum and mean reversion tendencies can also be modeled to optimize the timing of trades.

Regression analysis can model left tail risks by regressing drawdowns, volatility spikes, skew, kurtosis, etc., on market and macro factors. This quantifies how severely each asset is impacted under large market sell-offs, enabling the overweighting of assets with less downside risk.

The sensitivity of each asset to risk factors like interest rates and currencies can be modeled with regression. This determines appropriate hedging positions using derivatives like swaps, futures, and options to mitigate risks.

Regressing asset returns on factors like volatility and sentiment helps identify conditions predictive of impending drawdowns or crashes. Portfolios reduce risk preemptively based on these indicators before crashes materialize.

However, linear models do have limitations. Relationships between asset classes are often nonlinear, and structural breaks like policy regime shifts occur. Rare tail events are challenging to model accurately.

### What Are the Common Variables and Factors Used in Linear Regression Analysis for Stock Market Investments?

Linear regression analysis in stock market investments involves the utilization of a variety of common variables and factors to model the relationship between stock returns and potential drivers. These variables play a crucial role in understanding historical correlations and guiding investment decisions. Market risk factors are among the most fundamental variables used in regression models. They include the market return, which reflects overall market performance, often tracked using indices like the S&P 500. Additionally, the size factor considers the size of companies, with small-cap stocks often outperforming large-cap stocks, while the value factor compares stocks based on valuation multiples, indicating whether they are undervalued or overvalued. Another significant factor is the momentum factor, which indicates whether stocks that have performed well recently will continue to outperform.

### Macroeconomic variables

Macroeconomic variables also play a critical role in regression analysis for stock market investments. These variables include GDP growth, which represents economic expansion or contraction and impacts corporate earnings and stock returns. Interest rates affect the discounting of future cash flows and influence stock valuations, while inflation measures the rate of price increase, affecting the real value of future cash flows. Industrial production reflects the output of the manufacturing sector and overall economic health, while the unemployment rate indicates the health of the labor market and consumer spending power. Additionally, oil prices impact sectors dependent on oil, influencing their revenues and profits.

#### Sector and industry factors

The Sector and industry factors are essential considerations in regression analysis. Sector returns consider industry-specific trends alongside broader market movements, while industry classification groups stocks based on their industry, accounting for sector-specific performance. Commodity prices are significant for industries reliant on commodities, such as energy and materials.

#### Company-specific factors

Company-specific factors provide insights into individual stock performance. These factors include the earnings yield, indicating the relationship between a company’s earnings and its stock price, and the book-to-market ratio, which compares a company’s book value to its market value, offering insights into its valuation. Sales growth reflects the growth trajectory of a company’s revenue over time, while return on equity measures a company’s profitability relative to its shareholders’ equity. Momentum indicates whether a company’s stock price has been trending upward or downward, while earnings surprise reflects a company’s performance relative to analyst expectations.

Regression models also incorporate technical indicators like moving averages and price-volume trends to capture market sentiment and trends. These variables are used to estimate stock returns and understand their relationship with various market factors, guiding investment strategies and risk management decisions.

### What Are the Different Types of Linear Regression Models Used in Stock Market Analysis?

#### Simple Linear Regression

Simple linear regression involves modeling the relationship between a stock’s returns and a single factor, such as the market return or a specific risk factor. This model assumes a linear relationship between the dependent variable (stock returns) and one independent variable (the factor). For example, it can be used to examine how a stock’s monthly returns are influenced by the monthly returns of a broad market index like the S&P 500. The model estimates coefficients to minimize the sum of squared errors between predicted and actual returns, with the β1 coefficient representing the sensitivity of the stock to market movements. Simple linear regression is useful for understanding the impact of one factor on stock returns and for making predictions based on historical data.

#### Multiple Linear Regression

Multiple linear regression allows for the simultaneous modeling of the impact of multiple independent variables on stock returns. This provides a more comprehensive analysis by accounting for various drivers of returns beyond just the market. The model estimates coefficients for each independent variable, quantifying their impact on stock returns while controlling for other factors. Common independent variables in multiple linear regression models include macroeconomic factors, industry/sector returns, risk factors, fundamental ratios, and technical indicators. Multiple linear regression helps identify the most significant predictors of stock returns and evaluates the overall fit of the model using metrics like R-squared. However, it’s essential to avoid overfitting by selecting only the most relevant variables for the model.

In summary, simple linear regression is useful for analyzing the relationship between a stock’s returns and a single factor, while multiple linear regression provides a more comprehensive analysis by considering multiple factors simultaneously. Both types of regression models play a crucial role in stock market analysis and help investors make informed decisions based on historical data and predictive modeling.

### How Does Multicollinearity Impact Linear Regression Analysis in The Stock Market?

Multicollinearity, characterized by high correlation between two or more independent variables in a multiple regression model, presents challenges in interpreting results and assessing model performance in stock market analysis.

When independent variables are highly correlated, it becomes challenging to isolate the individual effect of each variable on the dependent variable (stock returns). Coefficients of collinear variables become unstable and difficult to estimate accurately, leading to wide swings in estimates with minor changes in data.

For instance, valuation ratios like the price-to-earnings (P/E) ratio and price-to-book (P/B) ratio often exhibit high correlation. Including both in a regression model may not provide precise insights into the isolated influence of each ratio on stock returns.

Moreover, high multicollinearity inflates the standard errors of coefficient estimates, making it harder to determine their statistical significance. Collinear variables may appear insignificant even if jointly they possess strong explanatory power.

In the presence of multicollinearity, while the overall fit of the model may seem satisfactory based on a high R-squared value, the estimates of individual coefficients and associated statistical tests become unreliable, thereby reducing the predictive accuracy of the model.

Common remedies for addressing multicollinearity in stock market regression analysis include:

1. Removing Highly Correlated Variables: Retain only one of the collinear variables based on economic logic and prior research, discarding redundant variables.
2. Obtaining More Data: Increasing the size of the data sample can enhance coefficient estimation for collinear variables, providing more reliable estimates.
3. Applying Regularization Techniques: Techniques such as ridge regression and LASSO introduce penalty terms to shrink unstable coefficient estimates towards zero, mitigating the impact of multicollinearity.
4. Using Principal Components Analysis (PCA): Instead of directly using correlated variables, PCA generates principal components, which are linear combinations of variables that are orthogonal and uncorrelated, effectively addressing multicollinearity.
5. Leveraging Economic Logic: Relying on economic theory to guide the interpretation of coefficients on correlated variables, emphasizing substantive insights over purely statistical estimates.

While multicollinearity may not pose a significant issue if the regression’s objective is forecasting stock returns, it necessitates careful handling of coefficient estimates and statistical inference to ensure the reliability and robustness of the model.

### How Can Outliers Affect the Results of Linear Regression Analysis in Stock Market Forecasting?

Outliers, which are data points significantly distant from the majority of observations, can exert a notable influence on the results of linear regression models utilized for stock market forecasting.

These outliers can manifest in stock market data due to various factors, including temporary volatility spikes, data errors, or extreme events such as market crashes or recessions. For instance, a sudden and drastic decline in a stock price during a market downturn could be identified as an outlier relative to its typical range of returns.

Incorporating outliers into the fitting of a linear regression model can substantially alter the regression line, pulling it towards these extreme data points. Consequently, the accuracy and precision of the model in representing the typical relationship between variables for the majority of observations are compromised.

Outliers with high leverage exert a disproportionate influence on the slope of the regression line, distorting the magnitude of coefficients that represent the relationships between variables. Furthermore, the presence of outliers can pull the intercept of the regression line towards these extreme points.

Consequently, predictions generated by the regression equation become less reliable for most data points, except for the outliers themselves. This can result in skewed forecasts that are overly sensitive to the presence of outliers.

For example, if a regression model includes a historical outlier associated with high inflation during a crisis in the 1980s, it may overestimate the impact of inflation on stock returns. Consequently, predictions based on normal inflation ranges could be distorted due to this historical anomaly.

Moreover, outliers contribute to increased variability and reduced overall model fit. As outliers are not adequately represented by the model, the coefficient of determination (R-squared) decreases, and standard errors increase, thereby diminishing the reliability of coefficient estimates.

In conclusion, outliers can significantly impact the results of linear regression analysis in stock market forecasting by distorting the regression line, influencing coefficient estimates, and reducing the overall reliability and accuracy of the model. Therefore, it is essential to identify and appropriately handle outliers to ensure the robustness of the regression analysis.

### Can I Generate Linear Regression Analysis in Excel?

Yes, you can easily conduct linear regression analysis in Excel using the built-in Data Analysis Toolpak. Here’s a simple guide on how to do it:

First, activate the Data Analysis Toolpak add-in if it is not already enabled. Go to File > Options > Add-ins and manage Excel add-ins to turn on Analysis Toolpak.

Next, organize your data with the dependent variable (y) in one column and independent variable(s) (x) in adjacent columns. The data should not contain any empty cells. Label the columns appropriately.

Then go to the Data tab in the toolbar and click Data Analysis. In the popup window, select Regression from the list and click OK.

In the Regression dialog box, input the y and x ranges. Check the appropriate options for labels, confidence intervals, etc. Click OK and Excel will output a results table on a new worksheet with the regression statistics including coefficients, R-squared, standard errors, t-stats, and p-values.

The built-in Excel regression tool makes it easy to quickly analyze and visualize linear relationships between variables. The results are sometimes used to predict the dependent variable from the independent variables based on the calculated equation.

### Can I Generate Linear Regression Analysis on Mat Lab?

Yes, MATLAB offers robust capabilities for conducting linear regression analysis. The Statistics and Machine Learning ToolboxTM within MATLAB encompasses a range of functions specifically designed for fitting linear models. These include functions like fitlm, stepwiselm, lasso, ridge, and others, which facilitate the process of building and analyzing linear regression models efficiently and effectively.

### Is Linear Regression Used to Identify Key Price Points, Entry Prices, Stop-Loss Prices, and Exit Prices?

Yes, linear regression is used in financial analysis to find critical price levels, like entry points, stop-loss levels, and exit prices. It analyzes the relationship between price and factors such as volume or time to identify significant price points that act as support or resistance levels. Traders use these levels to make decisions about trades and set stop-loss orders. However, it’s essential to use linear regression alongside other indicators and strategies for robust trading decisions.