/*! 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} Problem 97 Do you have ESP? A researcher lo... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Do you have ESP? A researcher looking for evidence of extrasensory perception (ESP) tests 500 subjects. Four of these subjects do significantly better (P 0.01) than random guessing. (a) Is it proper to conclude that these four people have ESP? Explain your answer. (b) What should the researcher now do to test whether any of these four subjects have ESP?

Short Answer

Expert verified
(a) No, statistical significance alone does not imply ESP. (b) Conduct controlled, unbiased experiments to confirm ESP.

Step by step solution

01

Understanding the Statistical Significance

The exercise involves determining if four individuals, out of 500 tested, who performed significantly better than random guessing actually possess ESP based on a statistical significance value of \( P = 0.01 \). This means there's only a 1% chance that any individual's performance at this level is due to random guessing.
02

Interpreting Statistical Results

While the four subjects performed significantly better with \( P = 0.01 \), this does not prove they have ESP. Statistical significance alone does not confirm causality, just the improbability of random occurrence. Multiple hypothesis testing in large samples can yield seemingly significant results by chance.
03

Moving to Step (a) Decision

Based on statistical interpretation alone, it is improper to conclude that the four individuals have ESP. More evidence is needed beyond statistical significance, as random chance can lead to similar results within large samples.
04

Preparing for Additional Testing

To further investigate whether the four subjects possess ESP, new tests should be conducted. These tests should be structured to rule out other explanations, like guessing patterns or psychological biases, and should be designed to replicate initial findings consistently.
05

Design of New Experiments (Step b)

Create controlled experiments that eliminate external variables that might influence results. Use methods like double-blind testing where neither subjects nor testers know the 'right' answers beforehand, to minimize potential biases.

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 91Ó°ÊÓ!

Key Concepts

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

Extrasensory Perception (ESP)
Extrasensory Perception, or ESP, refers to the ability to gain information or perceive things beyond the known human senses. Imagine knowing the outcome of an event or sensing something from a distance without any logical explanation. That's what ESP proposes. Understanding ESP involves exploring phenomena such as telepathy, clairvoyance, and precognition. While intriguing, ESP is surrounded by skepticism, mainly because scientific methods struggle to verify its existence. Scientists aim to understand if ESP truly exists or if reported outcomes arise from psychological factors or simple coincidences. For the researcher in the exercise, demonstrating ESP means observing results beyond random events consistently. It implies achieving outcomes that cannot be explained by chance, basic guessing, or any known logical reasoning. However, declaring four individuals have ESP based only on statistical significance can be misleading, as other factors might influence outcomes.
Hypothesis Testing
Hypothesis testing is a statistical process used to determine the likelihood that a certain hypothesis is true. It works by comparing observed data against what we'd expect if a certain assumption were true, known as the null hypothesis. In the context of ESP research, the null hypothesis could be that all outcomes are due to random guessing, with no real extrasensory phenomenon at play. The alternative hypothesis would argue that some subjects truly possess ESP. The test's goal is to see if the data collected offers enough evidence to reject the null hypothesis. If the test results show rare outcomes under the assumption of randomness, we might consider alternatives—or other explanations for these rare outcomes—essentially asking, "Could there be more than just chance at play?"
P-value
The P-value is a critical concept in hypothesis testing. It quantifies the probability of obtaining a result at least as extreme as the observed data, assuming the null hypothesis is true. In the ESP exercise, a P-value of 0.01 indicates there's only a 1% chance the observed results could occur under the null hypothesis of random guessing. While this suggests a strong departure from randomness, a low P-value alone doesn't confirm ESP. A small P-value can occur due to random variability, especially in large sample sizes where multiple testing increases the chance of rare events. The exercise teaches us that, while significant, the P-value is a measure of statistical improbability rather than definitive proof of ESP. Hence, further investigation and replication are necessary.
Controlled Experiments
Controlled experiments are crucial in scientific research to minimize bias and external influences. They ensure the reliability of findings by comparing results under different, isolated conditions. When testing for ESP, it's important to eliminate potential confounding factors that could skew results. This involves creating an environment where neither the experimenter nor the participant knows the outcome beforehand—a method known as double-blind testing. Controlled experiments help rule out other explanations for unusual findings and aim to replicate significant results consistently. By using this approach, researchers can better test the existence of ESP in the subjects who performed well in previous tests, leading to more definitive conclusions.

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

Anemia For the study of Jordanian children in Exercise 4, the sample mean hemoglobin level was 11.3 g/dl and the sample standard deviation was 1.6 g/dl. A significance test yields a P-value of 0.0016. (a) Interpret the P-value in context. (b) What conclusion would you make if \(\alpha=0.05 ?\) \(\alpha=0.017\) Justify your answer.

Taking stock An investor with a stock portfolio worth several hundred thousand dollars sued his broker due to the low returns he got from the portfolio at a time when the stock market did well overall. The investor’s lawyer wants to compare the broker’s performance against the market as a whole. He collects data on the broker’s returns for a random sample of 36 weeks. Over the 10-year period that the broker has managed portfolios, stocks in the Standard & Poor’s 500 index gained an average of 0.95% per month. The Minitab output below displays descriptive statistics for these data, along with the results of a significance test. (a) Determine whether there are any outliers. Show your work. (b) Interpret the P-value in context. (c) Do these data give convincing evidence to support the lawyer’s case? Carry out a test to help you answer this question.

Explain why we aren’t safe carrying out a one-sample z test for the population proportion p. No test A college president says, "99\% of the alumni support my fring of Coach Boggs." You contact an SRS of 200 of the college's \(15,000\) living alumni to test the hypothesis \(H_{0} : p=0.99\)

One-sided test Suppose you carry out a significance test of \(H_{0} : \mu=5\) versus \(H_{a} : \mu>5\) based on a sample of size \(n=20\) and obtain \(t=1.81\) (a) Find the P-value for this test using (i) Table B and (ii) your calculator. What conclusion would you draw at the 5% significance level? At the 1% significance level? (b) Redo part (a) using an alternative hypothesis of \(H_{a} : \mu \neq 5\)

Better parking A local high school makes a change that should improve student satisfaction with the parking situation. Before the change, 37% of the school’s students approved of the parking that was provided. After the change, the principal surveys an SRS of 200 of the over 2500 students at the school. In all, 83 students say that they approve of the new parking arrangement. The principal cites this as evidence that the change was effective. Perform a test of the principal's claim at the \(\alpha=0.05\) significance level.

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.