What is the level of significance of a test?

Question

BlackTom AI · Accepted Answer

The first step is to acknowledge that the provided data for answer options is missing, so we cannot analyze each choice individually. Nonetheless, we can restate and address the core concept in the question.

What is the level of significance of a test? In hypothesis testing, the level of significance, often denoted alpha, represents the probability of making a Type I error. A Type I error occurs when we reject the null hypothesis even though it is true. In other words, alpha is the pre-specified threshold for how willing we are to conclude that an effect exists when there actually isn’t one.

To illustrate, if a test has alpha = 0.05, there is a 5% chance of incorrectly rejecting the null when it is true. This does not depend on the sample data beyond the fact that alpha is chosen before collecting the data; it is a property of the testing procedure.

Common misconceptions: some might think the level of significance is the probability that the null hypothesis is true, which is incorrect. It is not about the truth of the hypothesis given the data, but about the long-run rate of false positives when the null is true. Another misconception is confusing alpha with the p-value; the p-value is the observed probability of obtaining data as extreme as (or more extreme than) what was observed, assuming the null is true, whereas alpha is a fixed threshold used to decide whether to reject.

In summary, the level of significance is the pre-set probability of rejecting a true null hypothesis, i.e., the chance of a Type I error associated with the test procedure.

stat_400_120258_253926 PA14-1

What is the level of significance of a test?

View Explanation

Log in for full answers

Similar Questions

Question at position 14 A Type I error is committed when _________________.the validity of a claim was rejecteda true null hypothesis is rejectedthe critical value is greater than the value of the test statistica true alternative hypothesis is not acceptedClear my selection

The significance level in a hypothesis test corresponds to the maximum probability that

A two-sample t-test was conducted at the 𝛼 = 0.01 level of significance to determine if full scale IQ differs between children whose blood-lead levels <40 mg/100ml and children whose blood-lead levels > 40 mg/100ml. What is the probability of committing a Type I error?

What type of error might we have made? Explain what the error means in the context of the application.

More Practical Tools for International Students

Exam Browser Assistant

Stylized Writing Assistant

Plagiarism Checker Assistant

Citation Assistant

In-Class Translation Assistant

Class Notes Assistant

Quiz Search Assistant

Past Exam Questions by School

Smart Practice Assistant

Adaptive Practice

Making Your Study Simpler