/*! 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 R4.11. How long did I work? A psycholog... [FREE SOLUTION] | 91影视

91影视

How long did I work? A psychologist wants to know if the difficulty of a task influences our estimate of how long we spend working at it. She designs two sets of mazes that subjects can work through on a computer. One set has easy mazes and the other has hard mazes. Subjects work until told to stop (after 6 minutes, but subjects do not know this). They are then asked to estimate how long they worked. The psychologist has 30 students available to serve as subjects.

(a) Describe an experiment using a completely randomized design to learn the effect of difficulty on estimated time.

(b) Describe a matched pairs experimental design using the same 30 subjects.

(c) Which design would be more likely to detect a difference in the effects of the treatments?

Explain.

Short Answer

Expert verified

Part (a) It is necessary to compare two therapeutic groups.

Part (b) Now shuffle all of the slips and assign them to the pupils to choose from. Compare their times now.

Part (c) since it is in charge of regulating the disparities between the 30 subjects

Step by step solution

01

Part (a) Step 1: Given information

Number of students are 30

02

Part (a) Step 2: Concept

The random assignment method assigns subjects to treatments based on chance. Before the treatments are applied, random assignment establishes treatment groups that are comparable (except for chance variance). In experiments, randomization and comparison combined prevent bias or systematic favoritism.

03

Part (a) Step 3: Explanation

There are 30 pupils in total.

There are two types of maze treatments: easy and challenging.

Assign a number between one and thirty pupils. Give 15 pupils an easy maze and the remaining 15 students tougher mazes. The results of the two therapy groups should then be compared.

04

Part (b) Step 1: Explanation

Make 15 slips and write a simple maze on each one. Similarly, make 15 more slips and write a difficult maze on them. Now shuffle all of the slips and assign them to the pupils to choose from. Compare their times now.

05

Part (c) Step 1: Explanation

Because it is controlling the differences among the 30 participants, the matched pair is likely to detect the difference.

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

Random digits Which of the following statements are true of a table of random digits, and which are false? Briefly explain your answers.

(a) There are exactly four 0s in each row of 40 digits.

(b) Each pair of digits has a chance 1/100 of being 00

(c) The digits 0000 can never appear as a group

because this pattern is not random.

Pain relief study Fizz Laboratories, a pharmaceutical company, has developed a new drug for relieving chronic pain. Sixty patients suffering from arthritis and needing pain relief are available. Each patient will be treated and asked an hour later, 鈥淎bout what percent of pain relief did you experience?鈥

(a) Why should Fizz not simply administer the new drug and record the patients鈥 responses?

(b) Should the patients be told whether they are getting the new drug or a placebo? How would this knowledge probably affect their reactions?

Who goes to the convention? A club has 30 student members and 10 faculty members. The students are

The club can send 4 students and 2 faculty members to a convention. It decides to choose those who will go by random selection. How will you label the two strata? Use Table D, beginning at line 123 to choose a stratified random sample of 4 students and 2 faculty members.

More rain for California? The changing climate will probably bring more rain to California, but we don鈥檛 know whether the additional rain will come during the

winter wet season or extend into the long dry season in spring and summer. Kenwyn Suttle of the University of California at Berkeley and his coworkers carried

out an experiment to study the effects of more rain in either season. They randomly assigned plots of open grassland to three treatments: added water equal to 20%of annual rainfall either during January to March (winter) or during April to June (spring), and no added water (control). Thirty-six circular plots of area 70square meters were available (see the photo), of which 18were used for this study. One response variable was total plant biomass, in grams per square meter, produced in a plot over a year.

(a) Outline the design of the experiment. What is this type of design called?

(b) Explain how you would randomly assign the experimental units to the three treatments. Then carry out your random assignment.

Sleepless nights How much sleep do high school students get on a typical school night? An interested student designed a survey to find out. To make data collection easier, the student surveyed the first 100 students to arrive at school on a particular morning. These students reported an average of 7.2 hours of sleep on the previous night.

(a) What type of sample did the student obtain?

(b) Explain why this sampling method is biased. Is 7.2 hours probably higher or lower than the true average amount of sleep last night for all students at the

school? Why?

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.