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. Why do we need regression analysis Why not simply use the mean value of the regressand as its best value?
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∙ 8y ago
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What is regression coefficient and correlation coefficient?
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.
What is the difference between multiple regression and logistic regression?
In cases wherethe dependent variable can take any numerical value for a given set of independent variables multiple regression is used.But in cases when the dependent variable is qualitative(dichotomous,polytomous)then logistic regression is used.In Multiple regression the dependent variable is assumed to follow normal distribution but in case of logistic regression the dependent variablefollows bernoulli distribution(if dichotomous) which means it will be only0 or 1.
What you mean by residual value?
The point lies one unit above the regression line.
What does the y-intercept represent in a linear regression equation?
It represents the value of the y variable when the x variable is zero.
What is a linear regression?
Suppose you have n objects and for each object you have observations for k+1 variables, X1, X2, ... , Xk and Y.Then a linear regression is an equation of the form E(y) = a + b1x1 + b2x2 + ... + bkxk where E(y) is the expected value of the variable Y when Xi has the value xi; and where a, and b1, b2, ... , bk are constants.
What is the roll of p-value in regression analysis?
It is a measure of how likely the observed values (or those more extreme) are under the assumptions of the regression model.
What is p value in regression analysis?
The p value is NOT a probability but a likelihood. It tells you the likelihood that the coefficient of a variable in regression is non zero. The p-value is: The probability of observing the calculated value of the test statistic if the null hypothesis is true
Why not simply use the mean value of the regressand as its best value?
Variance" is a mesaure of the dispersion of the probability distribution of a random variable. Consider two random variables with the same mean (same aver-age value). If one of them has a distribution with greater variance, then, roughly speaking, the probability that the variable will take on a value far from the mean is greater.
In a regression analysis if the mean value of y is related negatively of the value of x then larger values of x is associated with?
If the value (not mean value) of y is related negatively to the value of x then larger values of x are associated with smaller values of y.
How do you do a cosine regression on a graphic calculator?
I don't believe the graphic calculator has a cosine regression tool, but if you go to STAT, and CALC, there is a sin regression tool. If you hit enter on that then insert your L values, it will come up with a sin regression. The sin regression should be the same as a cosine regression, except that the sin regression should have a different value of C, usually getting rid of the value of C altogether will give you the correct regression.
Can anyone tell what is important in regression analysis?
The question is vague. Regression can be a complex analysis, and which information is important depends greatly on what you are using the results for. But very generally, if you are using regression as a hypothesis test, then the F (test statistic), r-square (effect size), and p (significance level), will be important. If you are using regression for predicting a value of Y based on X, then the slope of the regression line (b) and its intercept with the Y axis (a) are needed for the regression equation: Y = a + bX. Computer programs such as SPSS also test the statistical significance of both the intercept and the slope by comparing them to zero, and they will report several other numbers related to these tests. However, this may or may not be information that the researcher is interested in. Again, it all depends on the situation.
What is regression coefficient and correlation coefficient?
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.
How is linear regression used?
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.
What is the difference between correlation analysis and?
Correlation analysis is a type of statistical analysis used to measure the strength of the relationship between two variables. It is used to determine whether there is a cause-and-effect relationship between two variables or if one of the variables is simply related to the other. It is usually expressed as a correlation coefficient a number between -1 and 1. A positive correlation coefficient means that the variables move in the same direction while a negative correlation coefficient means they move in opposite directions.Regression analysis is a type of statistical analysis used to predict the value of one variable based on the value of another. This type of analysis is used to determine the relationship between two or more variables and to determine the direction strength and form of the relationship. Regression analysis is useful for predicting future values of the dependent variable given a set of independent variables.Correlation Analysis is used to measure the strength of the relationship between two variables.Regression Analysis is used to predict the value of one variable based on the value of another.
The value 11.7 represents the of the graph of the following linear regression equation?
slope
How do you perform a percent change analysis?
First, subtract the old value from the new value and then divide by the old value. Then you simply multiply that by a hundred and slap a percentage symbol on it. Hope I helped. -----Shawn
How does a linear regression allow us to better estimate trends costs and other factors in complex situations?
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.
