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Linear regression can be used in statistics in order to create a model out a dependable scalar value and an explanatory variable. Linear regression has applications in finance, economics and environmental science.

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I want to develop a regression model for predicting YardsAllowed as a function of Takeaways, and I need to explain the statistical signifance of the model.

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Ridge regression is used in linear regression to deal with multicollinearity. It reduces the MSE of the model in exchange for introducing some bias.

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The value depends on the slope of the line.

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in general regression model the dependent variable is continuous and independent variable is discrete type.

in genral regression model the variables are linearly related.

in logistic regression model the response varaible must be categorical type.

the relation ship between the response and explonatory variables is non-linear.

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Regression :The average Linear or Non linear relationship between Variables.

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There are many possible reasons. Here are some of the more common ones:

The underlying relationship is not be linear.

The regression has very poor predictive power (coefficient of regression close to zero).

The errors are not independent, identical, normally distributed.

Outliers distorting regression.

Calculation error.

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One of the main reasons for doing so is to check that the assumptions of the errors being independent and identically distributed is true. If that is not the case then the simple linear regression is not an appropriate model.

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A correlation coefficient close to 0 makes a linear regression model unreasonable. Because If the correlation between the two variable is close to zero, we can not expect one variable explaining the variation in other variable.

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George Portides has written:

'Robust regression with application to generalized linear model'

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The strength of linear regression lies in its simplicity and interpretability, making it easy to understand and communicate results. It is effective for identifying linear relationships between variables and can be used for both prediction and inference. However, its weaknesses include assumptions of linearity, homoscedasticity, and normality of errors, which can lead to inaccurate results if these assumptions are violated. Additionally, linear regression is sensitive to outliers, which can disproportionately influence the model's parameters.

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O. A. Sankoh has written:

'Influential observations in the linear regression model and Trenkler's iteration estimator' -- subject(s): Regression analysis, Estimation theory

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+ Linear regression is a simple statistical process and so is easy to carry out.

+ Some non-linear relationships can be converted to linear relationships using simple transformations.

- The error structure may not be suitable for regression (independent, identically distributed).

- The regression model used may not be appropriate or an important variable may have been omitted.

- The residual error may be too large.

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Linear Regression is a method to generate a "Line of Best fit" yes you can use it, but it depends on the data as to accuracy, standard deviation, etc.

there are other types of regression like polynomial regression.

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You can conclude that there is not enough evidence to reject the null hypothesis. Or that your model was incorrectly specified.

Consider the exact equation y = x2. A regression of y against x (for -a < x < a) will give a regression coefficient of 0. Not because there is no relationship between y and x but because the relationship is not linear: the model is wrong! Do a regression of y against x2 and you will get a perfect regression!

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on the line

Given a linear regression equation of = 20 - 1.5x, where will the point (3, 15) fall with respect to the regression line?

Below the line

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In a linear regression model, the y-intercept represents the expected value of the dependent variable (y) when the independent variable (x) is equal to zero. It indicates the starting point of the regression line on the y-axis. Essentially, it provides a baseline for understanding the relationship between the variables, although its interpretation can vary depending on the context of the data and whether a value of zero for the independent variable is meaningful.

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A linear regression model is a statistical method used to establish a relationship between a dependent variable and one or more independent variables through a linear equation. The model predicts the value of the dependent variable based on the values of the independent variables by fitting a straight line to the data points. The coefficients of the model indicate the strength and direction of the relationship, while the overall fit can be assessed using metrics like R-squared. It's widely used in various fields for prediction and analysis.

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ROGER KOENKER has written:

'L-estimation for linear models' -- subject(s): Regression analysis

'L-estimation for linear models' -- subject(s): Regression analysis

'Computing regression quantiles'

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Linear regression in R is a statistical method used to model the relationship between a dependent variable and one or more independent variables by fitting a linear equation to observed data. ANOVA (Analysis of Variance) in R is used to compare means across different groups to determine if there are any statistically significant differences. Both techniques can be easily implemented using functions like lm() for linear regression and aov() for ANOVA, allowing for efficient analysis of data relationships and group comparisons.

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I believe it is linear regression.

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When you use linear regression to model the data, there will typically be some amount of error between the predicted value as calculated from your model, and each data point. These differences are called "residuals". If those residuals appear to be essentially random noise (i.e. they resemble a normal (a.k.a. "Gaussian") distribution), then that offers support that your linear model is a good one for the data. However, if your errors are not normally distributed, then they are likely correlated in some way which indicates that your model is not adequately taking into consideration some factor in your data. It could mean that your data is non-linear and that linear regression is not the appropriate modeling technique.

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The goal of data re-expression in regression is to transform the response variable or predictors to improve the model's fit and meet the assumptions of linear regression. This can involve techniques such as logarithmic, square root, or polynomial transformations to stabilize variance, linearize relationships, or address issues like non-normality of residuals. By re-expressing the data, statisticians aim to enhance the interpretability and predictive power of the regression model.

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multiple correlation: Suppose you calculate the linear regression of a single dependent variable on more than one independent variable and that you include a mean in the linear model. The multiple correlation is analogous to the statistic that is obtainable from a linear model that includes just one independent variable. It measures the degree to which the linear model given by the linear regression is valuable as a predictor of the independent variable. For calculation details you might wish to see the wikipedia article for this statistic.

partial correlation: Let's say you have a dependent variable Y and a collection of independent variables X1, X2, X3. You might for some reason be interested in the partial correlation of Y and X3. Then you would calculate the linear regression of Y on just X1 and X2. Knowing the coefficients of this linear model you would calculate the so-called residuals which would be the parts of Y unaccounted for by the model or, in other words, the differences between the Y's and the values given by b1X1 + b2X2 where b1 and b2 are the model coefficients from the regression. Now you would calculate the correlation between these residuals and the X3 values to obtain the partial correlation of X3 with Y given X1 and X2. Intuitively, we use the first regression and residual calculation to account for the explanatory power of X1 and X2. Having done that we calculate the correlation coefficient to learn whether any more explanatory power is left for X3 to 'mop up'.

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Regression analysis is a statistical technique to measure the degree of linear agreement in variations between two or more variables.

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A scatter diagram visually represents the relationship between two variables, allowing you to observe patterns, trends, and potential correlations. By examining the shape of the data points, you can determine if the relationship is linear, quadratic, or exhibits another form. For instance, if the points roughly form a straight line, a linear regression may be appropriate; if they curve, a polynomial regression could be better suited. Additionally, the presence of clusters or outliers can inform the choice of regression model and its complexity.

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The linear regression function rule describes the relationship between a dependent variable (y) and one or more independent variables (x) through a linear equation, typically expressed as ( y = mx + b ) for simple linear regression. In this equation, ( m ) represents the slope of the line (indicating how much y changes for a one-unit change in x), and ( b ) is the y-intercept (the value of y when x is zero). For multiple linear regression, the function expands to include multiple predictors, represented as ( y = b_0 + b_1x_1 + b_2x_2 + ... + b_nx_n ). The goal of linear regression is to find the best-fitting line that minimizes the difference between observed and predicted values.

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They are used in statistics to predict things all the time. It is called linear regression.

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The strength of the linear relationship between the two variables in the regression equation is the correlation coefficient, r, and is always a value between -1 and 1, inclusive.

The regression coefficient is the slope of the line of the regression equation.

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Regression analysis describes the relationship between two or more variables. The measure of the explanatory power of the regression model is R2 (i.e. coefficient of determination).

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To create a regression model using a crate regression technique, follow these key steps:

  1. Define the research question and identify the variables of interest.
  2. Collect and prepare the data, ensuring it is clean and organized.
  3. Choose the appropriate regression model based on the type of data and research question.
  4. Split the data into training and testing sets for model evaluation.
  5. Fit the regression model to the training data and assess its performance.
  6. Evaluate the model using statistical metrics and adjust as needed.
  7. Use the model to make predictions and interpret the results.

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difference between correlation and regression?

(1) The correlation answers the STRENGTH of linear association between paired variables, say X and Y. On the other hand, the regression tells us the FORM of linear association that best predicts Y from the values of X.

(2a) Correlation is calculated whenever:

* both X and Y is measured in each subject and quantify how much they are linearly associated.

* in particular the Pearson's product moment correlation coefficient is used when the assumption of both X and Y are sampled from normally-distributed populations are satisfied

* or the Spearman's moment order correlation coefficient is used if the assumption of normality is not satisfied.

* correlation is not used when the variables are manipulated, for example, in experiments.

(2b) Linear regression is used whenever:

* at least one of the independent variables (Xi's) is to predict the dependent variable Y. Note: Some of the Xi's are dummy variables, i.e. Xi = 0 or 1, which are used to code some nominal variables.

* if one manipulates the X variable, e.g. in an experiment.

(3) Linear regression are not symmetric in terms of X and Y. That is interchanging X and Y will give a different regression model (i.e. X in terms of Y) against the original Y in terms of X.

On the other hand, if you interchange variables X and Y in the calculation of correlation coefficient you will get the same value of this correlation coefficient.

(4) The "best" linear regression model is obtained by selecting the variables (X's) with at least strong correlation to Y, i.e. >= 0.80 or <= -0.80

(5) The same underlying distribution is assumed for all variables in linear regression. Thus, linear regression will underestimate the correlation of the independent and dependent when they (X's and Y) come from different underlying distributions.

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No, the slope of a line in linear regression cannot be positive if the correlation coefficient is negative. The correlation coefficient measures the strength and direction of a linear relationship between two variables; a negative value indicates that as one variable increases, the other decreases. Consequently, a negative correlation will result in a negative slope for the regression line.

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You question is how linear regression improves estimates of trends. Generally trends are used to estimate future costs, but they may also be used to compare one product to another. I think first you must define what linear regression is, and what the alternative forecast methods exists. Linear regression does not necessary lead to improved estimates, but it has advantages over other estimation procesures. Linear regression is a mathematical procedure that calculates a "best fit" line through the data. It is called a best fit line because the parameters of the line will minimizes the sum of the squared errors (SSE). The error is the difference between the calculated dependent variable value (usually y values) and actual their value. One can spot data trends and simply draw a line through them, and consider this a good fit of the data. If you are interested in forecasting, there are many methods available. One can use more complex forecasting methods, including time series analysis (ARIMA methods, weighted linear regression, or multivariant regression or stochastic modeling for forecasting. The advantages to linear regression are that a) it will provide a single slope or trend, b) the fit of the data should be unbiased, c) the fit minimizes error and d) it will be consistent. If in your example, the errors from regression from fitting the cost data can be considered random deviations from the trend, then the fitted line will be unbiased. Linear regression is consistent because anyone who calculates the trend from the same dataset will have the same value. Linear regression will be precise but that does not mean that they will be accurate. I hope this answers your question. If not, perhaps you can ask an additional question with more specifics.

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true, liner regression is useful for modeling the position of an object in free fall

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Frank E. Harrell has written:

'Regression modeling strategies' -- subject(s): Regression analysis, Linear models (Statistics)

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how can regression model approach be useful in lean construction concept in the mass production of houses

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The linear regression algorithm offers a linear connection between an independent and dependent variable for predicting the outcome of future actions. It is a statistical method used in machine learning and data science forecast analysis.

For more information, Pls visit the 1stepgrow website

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In statistics, the Gauss-Markov theorem states that in a linear regression model in which the errors have expectation zero and are uncorrelated and have equal variances, the best linear unbiased estimator (BLUE) of the coefficients is given by the ordinary least squares (OLS) estimator, provided it exists.

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