/*! 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. 2 Early on, the most common treatm... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 3: Q. 2 (page 158)

Early on, the most common treatment for breast cancer was removal of the breast. It is now usual to remove only the tumor and nearby lymph nodes, followed by radiation. The change in policy was due to a large medical experiment that compared the two treatments. Some breast cancer patients, chosen at random, were given one or the other treatment. The patients were closely followed to see how long they lived following surgery. What are the explanatory and response variables? Are they categorical or quantitative?

Short Answer

Expert verified

The treatment is both explanatory and categorical, and the patient's post-surgical survival is both a reaction and a quantitative variable.

Step by step solution

01

Concept Introduction

In this problem, there are two variables to consider. The sort of treatment each patient received is the explanatory variable. The response variable would be the length of time each patient lived after surgery.

The explanatory variable can be regarded of as something that aids in the explanation or prediction of the response variable. The influence of the explanatory variable can be described by the response variable.

02

Explanation

The explanatory variable is a categorical variable because the treatment kind cannot be specified by a number. The response variable is quantitative since the number of years lived following surgery may be quantified given a number.

Quantitative variables have numerical values, but categorical variables place people into one of several classes.

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

The residual plot does not show a random scatter. Describe the pattern you see.

Stats teachers鈥� cars A random sample of AP Statistics teachers were asked to report the age (in years) and mileage of their primary vehicles. A scatterplot of the data, a least-squares regression printout, and a residual plot are provided below.

(a) Give the equation of the least-squares regression line for these data. Identify any variables you use.

(b) One teacher reported that her 6-year-old car had65,000 miles on it. Find its residual.

(c) Interpret the slope of the line in context.

(d) What鈥檚 the correlation between car age and mileage? Interpret this value in context.

(e) How well does the regression line fit the data? Justify your answer using the residual plot and s.

A government report looked at the amount borrowed for college by students who graduated in 2000and had taken out student loans.12 The mean amount was x=\(17,776and the standard deviation was sx=\)12,034. The median was\(15,532and the quartiles were Q1=\)9900and Q3=\(22,500.

(a) Compare the mean and the median. Also compare the distances of Q1 and Q3 from the median. Explain why both comparisons suggest that the distribution is right-skewed.

(b) The right-skew pulls the standard deviation up. So a Normal distribution with the same mean and standard deviation would have a third quartile larger than the actual Q3.Find the third quartile of the Normal distribution with渭=\)17,776and 蟽=\(12,034and compare it withQ3=\)22,500.

Late bloomers? Japanese cherry trees tend to blossom early when spring weather is warm and later when spring weather is cool. Here are some data on the average March temperature (in 掳C) and the day in April when the first cherry blossom appeared over a 24-year period:

(a) Make a well-labeled scatterplot that鈥檚 suitable for predicting when the cherry trees will bloom from the temperature. Describe the direction, form, and strength of the relationship.

(b) Use technology to find the equation of the least-squares regression line. Interpret the slope and y the intercept of the line in this setting.

(c) The average March temperature this year was 3.5掳C When would you predict that the first cherry blossom would appear? Show your method clearly.

(d) Find the residual for the year when the average March temperature was 4.5掳C Show your work.

(e) Use technology to construct a residual plot. Describe what you see.

(f) Find and interpret the value of r2 and s in this setting.

In its Fuel Economy Guide for 2008 model vehicles, the Environmental Protection Agency gives data on 1152vehicles. There are a number of outliers, main vehicles with very poor gas mileage. If we ignore the outliers, however, the combined city and highway gas mileage of the other 1120

or so vehicles are approximately Normal with a mean of 18.7miles per gallon (mpg) and a standard deviation of 4.3 mpg.

The top 10%(2.2)How high must a 2008vehicle鈥檚 gas mileage be in order to fall in the top 10% of all vehicles? (The distribution omits a few high outliers, mainly hybrid gas-electric vehicles.)
See all solutions

Recommended explanations on Math Textbooks

Applied Mathematics

Read Explanation

Decision Maths

Read Explanation

Statistics

Read Explanation

Mechanics Maths

Read Explanation

Theoretical and Mathematical Physics

Read Explanation

Calculus

Read Explanation
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.