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Multiple choice: Select the best answer for Exercises 21 to 26. The equation of the least-squares regression line for predicting selling price from appraised value is Multiple choice: Select the best answer for Exercises 21 to 26. (a) \(\widehat{\text { price }}=79.49+0.1126\) (appraised value) (b) \(\widehat{\text { price }}=0.1126+1.0466\) (appraised value). (c) \(\widehat{\text { price }}=127.27+1.0466\) (appraised value). (d) \(\widehat{\text { price }}=1.0466+127.27\) (appraised value). (e) \(\widehat{\text { price }}=1.0466+69.7299\) (appraised value).

Short Answer

Expert verified
Option (c) is the correct equation: \( \hat{\text{price}} = 127.27 + 1.0466 \times \text{appraised value} \).

Step by step solution

01

Understand the Least Squares Regression Line

The least squares regression line is used to predict the dependent variable (selling price in this case) from the independent variable (appraised value). The formula is typically in the form of \( \hat{y} = b_0 + b_1x \), where \( \hat{y} \) is the predicted value, \( b_0 \) is the y-intercept, and \( b_1 \) is the slope of the line.
02

Identify Correct Regression Line Equation Format

The correct format of the equation should resemble \( \widehat{\text{price}} = \text{intercept} + (\text{slope}) \times (\text{appraised value}) \). Identify which of the given options uses this format.
03

Evaluate Each Option

Evaluate each option to see which one's format matches that of a standard least squares regression line equation. In this case, check: (a) follows the format one linear equation (b) places slope as constant which is incorrect (c) follows correct format (d) is incorrect format (e) is incorrect format.
04

Make Comparison

Based on the evaluations, option (c) \( \hat{\text{price}} = 127.27 + 1.0466 \times \text{appraised value} \) matches the format \( \hat{y} = b_0 + b_1x \), where 127.27 is the y-intercept and 1.0466 is the slope.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Regression Line Equation
The equation of the least squares regression line is essential in the context of predictive analytics. It provides a mathematical formula to forecast a dependent variable (like selling price) from an independent variable (such as appraised value). This formula generally follows the format: \( \hat{y} = b_0 + b_1x \). Here, \( \hat{y} \) represents the predicted outcome.
This structured equation illustrates the relationship between variables and allows us to make informed predictions based on data inputs.
By identifying the y-intercept and slope, one can effectively model and interpret real-world scenarios, improving decision-making across various domains.
Dependent and Independent Variables
Understanding the core idea of dependent and independent variables is crucial in regression analysis. In any predictive modeling task, we begin by identifying these variables. But what do these terms mean?
Here, the dependent variable is the outcome or the subject of prediction. It relies on other variables to provide its value. In the above scenario, this is the selling price of an item.
The independent variable, meanwhile, is the gauging factor that influences the prediction. This variable provides the input needed to forecast the dependent variable. In the given equation, the appraised value serves as the independent variable.
  • The dependent variable "depends" on the changes in the independent variable.
  • The independent variable is manipulated to observe effects on the dependent variable.
This distinction helps in constructing the regression line equation correctly and ensures clarity in predictive analysis.
Predictive Modeling
Predictive modeling is a powerful statistical tool used to forecast outcomes by evaluating patterns in data. By using historical and current data, these models provide a valuable look into future trends.
With least squares regression, predictive modeling allows for the estimation of relationships between variables, often used to guide decision-making in business and research. The process involves:
  • Selecting data for analysis.
  • Identifying relationships between dependent and independent variables.
  • Applying statistical models to predict future outcomes.
This approach is not only about computing equations; it's about gaining insights that drive informed decisions and strategies, enhancing the efficiency of processes across different fields.
Y-intercept and Slope
The concepts of y-intercept and slope are foundational in understanding the dynamics of a regression equation. These elements provide key insights into the nature of the relationship between variables.
The y-intercept is the starting point or baseline value of the dependent variable when the independent variable holds a value of zero. It's represented as \( b_0 \) in the regression equation.
The slope, denoted as \( b_1 \), illustrates the rate of change. It shows how the dependent variable moves with a unit increase in the independent variable. For example, a slope of 1.0466 suggests that for each unit increase in the appraised value, the selling price increases by 1.0466.
  • Y-intercept provides the baseline condition.
  • Slope indicates the rate of variability.
Understanding these components helps in forming a clear picture of the relationship between the studied variables, allowing predictions to be both accurate and meaningful.

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Most popular questions from this chapter

Exercises 46 to 48 refer to the following setting. Some high school physics students dropped a ball and measured the distance fallen (in centimeters) at various times (in seconds) after its release. If you have studied physics, then you probably know that the theoretical relationship between the variables is distance \(=490(\text { time })^{2}\) . A scatterplot of the students data showed a clear curved pattern. Which of the following single transformations should linearize the relationship? I. time^ \(^{2}\) II. distance \(^{2}\) III. \(\sqrt{\text { distance }}\) (a) I only (c) III only (e) I and III only (b) II only (d) I and II only

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