/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q. 1 Which of the following is not on... [FREE SOLUTION] | 91影视

91影视

Which of the following is not one of the conditions that must be satisfied in order to perform inference about the slope of a least-squares regression line? (a) For each value of x, the population of y-values is Normally distributed.

(b) The standard deviation of the population of y-values corresponding to a particular value of x is always the same, regardless of the specific value of x. (c) The sample size鈥攖hat is, the number of paired observations (x, y)鈥攅xceeds 30.

(d) There exists a straight line y=+xsuch that, for each value of x, the mean yof the corresponding population of y-values lies on that straight line.

(e) The data come from a random sample or a randomized experiment.

Short Answer

Expert verified

The condition that is satisfied in order to perform inference about the slope of a least-squares regression line is option (c) The sample size鈥攖hat is, the number of paired observations (x, y)鈥攅xceeds30.

Step by step solution

01

Concept introduction

A regression line is marked in statistics that best govern the relationship of a set of data. In other phrases, it's a line that best describes a data set's trend.

02

Explanation

Random, Normal, Independent, Linear, and Equal variance are the five requirements for inferring the slope of a least-squares regression line.

(a) Must be met because it is a standard requirement.

(b) Must be satisfied because it is a criterion for equal variance.

(c) Must not be satisfied because there is no sample size constraint.

(d) This condition must be met because it is a Linear requirement.

Because it is a Random criterion, it must be satisfied.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

In the casting of metal parts, molten metal flows through a 鈥済ate鈥 into a die that shapes the part. The gate velocity (the speed at which metal is forced through the gate) plays a critical role in die casting. A firm that casts cylindrical aluminium pistons examined a random sample of 12pistons formed from the same alloy of metal. What is the relationship between the cylinder wall thickness (inches) and the gate velocity (feet per second) chosen by the skilled workers who do the casting? If there is a clear pattern, it can be used to direct new workers or to automate the process. A scatterplot of the data is shown below

A least-squares regression analysis was performed on the data. Some computer output and a residual plot are shown below. A Normal probability plot of the residuals (not shown) is roughly linear.

Do these data provide convincing evidence of a straight-line relationship between thickness and gate velocity in the population of pistons formed from this alloy of metal? Carry out an appropriate significance test at the =0.05level.

Suppose that the relationship between a response variable y and an explanatory variable x is modelled by y=2.7(0.316)x. Which of the following scatterplots would approximately follow a straight line?

(a) A plot of y against x

(b) A plot of y against log x

(c) A plot of log y against x

(d) A plot of log y against log x

(e) None of (a) through (d)

We record data on the population of a particular country from 1960to 2010. A scatterplot reveals a clear curved relationship between population and year. However, a different scatterplot reveals a strong linear relationship between the logarithm (base 10) of the population and the year. The least-squares regression line for the transformed data is,

log ( population) =-13.5+0.01(years).

Based on this equation, the population of the country in the year 2020 should be about

(a)6.7

(b) 812

(c) 5,000,000

(d) 6,700,000

(e) 8,120,000.

Students in Mr. Handford鈥檚 class dropped a kickball beneath a motion detector. The detector recorded the height of the ball as it bounced up and down several times. Here are the heights of the ball at the highest point on the first five bounces:

Bounce numberHeight (feet)12.24021.62031.23540.95850.756

Here is the scatter plot of the data

(a) The following graphs show the results of two different transformations of the data. Would an exponential model or a power model provide a better description of the relationship between bounce number and height? Justify your answer.

(b) Minitab output from a linear regression analysis on the transformed data of log(height) versus bounce number is shown below. Give the equation of the least-squares regression line. Be sure to define any variables you use.

PredictorCoefSE CoefTPConstant0.453740.0138532.760.000Bounce-0.1171600.004176-28.060.000

S=0.0132043R-Sq=99.6%R-Sq(adj)=99.5%

(c) Use your model from part (b) to predict the highest point the ball reaches on its seventh bounce. Show your work.

(d) A residual plot for the linear regression in part (b) is shown below. Do you expect your prediction part (c) to be too high, too low, or just right? Justify your answer.

Marcella takes a shower every morning when she gets up. Her time in the shower varies according to a Normal distribution with mean 4.5minutes and standard deviation 0.9minutes.

(a) If Marcella took a 7-minute shower, would it be classified as an outlier? Justify your answer.

(b) Suppose we choose 10days at random and record the length of Marcella鈥檚 shower each day. What鈥檚 the probability that her shower time is 7minutes or higher on at least 2of the days? Show your work.

(c) Find the probability that the mean length of her shower times on these 10 days exceeds5 minutes. Show your work

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.