How to Check the non-constant variance using this ’residuals vs fitted values’ plot?

Q: Why is it important to use clustered standard errors for the regression?Do the results change if you…

A: Clustered Standard Errors occur when some observations in a data set are related to each other. It…

Q: Discuss how to choose the appropriate benchmark for performance evaluation USING REGRESSION R…

A: Using Regression R Squared

Q: How are the distribution of the observed residuals of the constructed model tested for normality?…

A: A normality plot (Q-Q plot) can be made along with the regression line for the obtained predicted…

Q: A study was performed on 64 female college athletes. Researchers collected data on each female…

A:

Q: Scores on a certain test are normally distributed with a variance of 70. A researcher wishes to…

A: From the given information, the confidence level is 0.95, the variance is 70 and the margin of error…

Q: The following regression output is for predicting the heart weight (in g) of cats from their body…

A: Given, R2=64.66%=0.6466 Coefficient of determination that is R square is the square of correlation…

Q: To estimate the value of a dependent variable based on the values of one or more independent…

A: Solution-: To estimate the value of a dependent variable based on the value of one or more…

Q: < Prev The table below gives the list price and the number of bids received for five randomly…

A: Slope is the change in the value of dependent variable for a unit value change in independent…

Q: n a sample of cars reviewed by Motor Trend magazine, the mean horsepower (hp) was 150 hp with a…

A: Given Information: The mean horsepower hp was 150 hp with a standard deviation of 36 hp. The mean…

Q: You want to look at an ANOVA table of a regression in which a dependent variable is predicted using…

A: The total number of observations is n = 7 and the F-ratio is, 15. The residual sum of squares is RSS…

Q: The correlation coefficient always moves between 0 and 1. True or False.

A: The correlation coefficient can be negative, zero or positive.

Q: The three pieces of information that the standard error for slope is dependent on in an inference of…

A:

Q: What is the expected average height of 8 year old boys, using the regression equation?

A: From the given information, the obtained regression equation is y=27.84+2.573x.

Q: What is the sample regression equation (round to 2 decimal places)? y =  +  Education +  Experience…

A: Regression equation is y=β0+β1Education+β2Experience+β3Age Here, β0=7.90, β1= 2.44, β2=0.54, β3= -…

Q: How is the number of degrees of freedom available for estimating , the variance of ε, related to the…

A: Let n be total number of variables       k be number of independent variables

Q: Why is the equation of the regression line for this scatter plot ?

A: The regression equation is, y=a+bx In the formula a is the intercept value, and x is the slope…

Q: Which is an assumption of linear regression analysis? The mean of the residuals should be

A: Please find the explanation below.

Q: sum of squared residuals?

A: Sum of square residual is also known as error sum of square. It is calculated by subtracting the…

Q: In linear regression, the mean value of all residuals will be greater for a correlation of -.70 than…

A: The mean (or expected) value of all residuals will be greater for correlation of -0.70 than for a…

Q: What can you say about autocorrelation of the residual? normality of the residuals? and the variance…

A: We can see from the first graph, there is positive autocorrelation.  An autocorrelation plot is…

Q: How to use simple linear regression model to find 90% confidence interval for the mean of y,…

A: Given, Confidence level = 90% for simple linear regression model of Y on X.

Q: The average exam score is 63 with a variance of 33.  Your exam has a Z score of 0.96. What is your…

A:

Q: Using your favorite statistics software package, you generate a scatter plot with a regression…

A: Given data, y=59.31x+26.22 r=0.161  proportion of the variation in y=?

Q: State true or false When a correlation coefficient for a linear regression model is close to -1 ,…

A: Given : Statement : When a correlation coefficient (corr. coeff.) for a linear regression(reg.)…

Q: True or False: The residual of a data point is the observed value minus the predicted value.

A: Introduction: The population regression model of a response variable y on explanatory variables, x1,…

Q: What happens to the sum of the squared residuals as the data gets closer versus farther from the…

A: The sum of squared residuals is SSE = Σ(y - ŷ)2, where y is the actual value of the response…

Q: You have these 3 histograms:  Histogram of Residuals: X-axis: Residual values (deviation between…

A: Student's t-distribution: When a sample of size 'n' is selected from normal distribution, the…

Q: A correlation of zero between two quantitative variables means that there is no association between…

A: Correlation:-  The Relation ship or     an association between two or more variables.    is…

Q: true or false. Explain In a fixed effects regression, the residuals (ûit) will be uncorrelated with…

A: The statement is true.

Q: What does it mean for a regression line to be the "best-fit" line.

A: The form of the simple linear regression line is given by,

Q: A data set includes weights of garbage discarded in one week from 62 different households. The…

A: Decision rule for linear correlation : If the test statistic is greater than the critical value then…

Q: What is a simple way to check for normality of residuals in a regression model?

A: First of all, testing of normality of residual is important for any regression model because it it…

Q: What is a “residuals plot” and how is it used in assessing linearity of calibration curves?

A: Residual plot is the graphical representation of the residuals of the regression model.

Q: )Based on the data, construct the sample regression function (SRF). ii) Calculate the residuals sum…

A: Given x y 5 5 9 6 11 8 14 9 18 10 20 11 24 12 25 14 27 15 28 16 30 18 32…

Q: dentify a characteristic of the data that is ignored by the regression line.

A: From the given results, it is observed that the scatter plot for the given data is option c.

Q: Use the value of the linear correlation coefficient to calculate the coefficient of determination.…

A: The value of correlation coefficient is r = -0.187 And the coefficient of determination is…

Q: in multiple regression analysis, a residual is the difference between the value of a dependent…

A: We know that, In any regression model, Residual is the difference between the value of a dependent…

Q: To determine if the listing price of a house influences the selling price; a financial analyst…

A: It is given that  Total observations, n = 50 No. of parameters, k = 2 SSR = 25818.5 SSE = 1341

Q: When calculating a correlation coefficient between two continuous variables, the scales on which the…

A: Correlation: By correlation we mean the association or interdependence between two variables. If two…

Q: Discuss the differences between an error and a residual.

A: Given : Two measures Error  Residual

Q: Compute the predicted value of IPT for the mean value of PSS (static facial expressions (higher…

A: Given: slope=0.148Intercept=3.085Mean of PSS=7.23 The regression equation is y=3.085+0.148x. The…

Q: ow are the overhead widths (in cm) of seals measured from photographs and the weights (in kg) of the…

A: Here from the given information we find correlation coefficient and test for it.

Q: a residual is the distance between the data value in the line of best fit true or false?

A: a residual is the distance between the data value in the line of best fit -True

Q: The correlation between first year college GPA and high school GPA is 0.683. If a simple linear…

A: Given information: The correlation between first year college GPA and high school GPA is 0.683. If a…

Correlation

Correlation defines a relationship between two independent variables. It tells the degree to which variables move in relation to each other. When two sets of data are related to each other, there is a correlation between them.

Linear Correlation

A correlation is used to determine the relationships between numerical and categorical variables. In other words, it is an indicator of how things are connected to one another. The correlation analysis is the study of how variables are related. 

Regression Analysis

Regression analysis is a statistical method in which it estimates the relationship between a dependent variable and one or more independent variable. In simple terms dependent variable is called as outcome variable and independent variable is called as predictors. Regression analysis is one of the methods to find the trends in data. The independent variable used in Regression analysis is named Predictor variable. It offers data of an associated dependent variable regarding a particular outcome.