Contents

- 1 What does decision mean in statistics?
- 2 What would be an appropriate decision rule?
- 3 How do you interpret statistical power?
- 4 What is decision errors in statistics?
- 5 How does statistics help in decision making?
- 6 What is decision making under risk?
- 7 What is disjunctive decision rule?
- 8 What is the rejection rule?
- 9 What is the decision rule in the Nhst approach?
- 10 What is statistical power and why is it important?
- 11 What is a good statistical power?
- 12 What is statistical power and effect size?
- 13 What is a Type 2 error example?
- 14 What’s the difference between Type I and type II error?
- 15 What is the difference between Type I and type II error?

## What does decision mean in statistics?

A decision rule is a procedure that the researcher uses to decide whether to accept or reject the null hypothesis. For example, a researcher might hypothesize that a population mean is equal to 10. He/she might collect a random sample of observations to test this hypothesis.

## What would be an appropriate decision rule?

The decision rule would be: if the observed data is in the rejection region, then reject H0. If not, we fail to reject H0. Note that it is not always the best way that we choose most extreme value as the cutoff value. Or else the world is simple.

## How do you interpret statistical power?

Simply put, power is the probability of not making a Type II error, according to Neil Weiss in Introductory Statistics. Mathematically, power is 1 – beta. The power of a hypothesis test is between 0 and 1; if the power is close to 1, the hypothesis test is very good at detecting a false null hypothesis.

## What is decision errors in statistics?

Decisions Errors refer to the probability of making a wrong conclusion when doing hypothesis testing. There are two ways a researcher can make a Decision Error. She can either decide that his hypothesis is true when it is actually false, or decide that his hypothesis is false when it is in fact true.

## How does statistics help in decision making?

Statistics can also aid the decision making process by enabling us to establish numerical benchmarks and monitor and evaluate the progress of our policy or program. Statistics can be used to inform decision making throughout the different stages of the policy-making process.

## What is decision making under risk?

When having knowledge regarding the states of nature, subjective probability estimates for the occurrence of each state can be assigned. In such cases, the problem is classified as decision making under risk. In the decision making process, all relevant information is evaluated through decision analysis (DA).

## What is disjunctive decision rule?

The disjunctive decision rule establishes a minimum level of performance for each important attribute (often a fairly high level). All brands that surpass the performance level for any key attribute are considered acceptable.

## What is the rejection rule?

A rejection rule is a logical condition or a restriction to the value of a data item or a data group which must not be met if the data is to be considered correct. In various connections other terms are used, e.g. Y-rule.

## What is the decision rule in the Nhst approach?

In the NHST framework, the level of significance is (in practice) assimilated to the alpha level, which appears as a simple decision rule: if the p-value is less or equal to alpha, the null is rejected. It is however a common mistake to assimilate these two concepts.

## What is statistical power and why is it important?

Statistical Power is the probability that a statistical test will detect differences when they truly exist. Think of Statistical Power as having the statistical “muscle” to be able to detect differences between the groups you are studying, or making sure you do not “miss” finding differences.

## What is a good statistical power?

Power refers to the probability that your test will find a statistically significant difference when such a difference actually exists. It is generally accepted that power should be. 8 or greater; that is, you should have an 80% or greater chance of finding a statistically significant difference when there is one.

## What is statistical power and effect size?

Statistical power is the probability that your study will find a statistically significant difference between interventions when an actual difference does exist. Like statistical significance, statistical power depends upon effect size and sample size.

## What is a Type 2 error example?

A type II error produces a false negative, also known as an error of omission. For example, a test for a disease may report a negative result, when the patient is, in fact, infected. This is a type II error because we accept the conclusion of the test as negative, even though it is incorrect.

## What’s the difference between Type I and type II error?

In statistics, a Type I error means rejecting the null hypothesis when it’s actually true, while a Type II error means failing to reject the null hypothesis when it’s actually false. This means that your results only have a 5% chance of occurring, or less, if the null hypothesis is actually true.

## What is the difference between Type I and type II error?

Type 1 error, in statistical hypothesis testing, is the error caused by rejecting a null hypothesis when it is true. Type II error is the error that occurs when the null hypothesis is accepted when it is not true.