## Null Hypothesis Definition | Investopedia

### Research Problem | Null Hypothesis | Hypothesis

As such, by taking a hypothesis testing approach, Sarah and Mike want to **generalize** their results to a population rather than just the students in their sample. However, in order to use hypothesis testing, you need to re-state your research hypothesis as a null and alternative hypothesis. Before you can do this, it is best to consider the process/structure involved in hypothesis testing and what you are measuring. This structure is presented .

### Nursing Research | Null Hypothesis | Hypothesis

In statistics terminology, the students in the study are the **sample** and the larger group they represent (i.e., all statistics students on a graduate management degree) is called the **population**. Given that the sample of statistics students in the study are representative of a larger population of statistics students, you can use hypothesis testing to understand whether any differences or effects discovered in the study exist in the population. In layman's terms, hypothesis testing is used to establish whether a research hypothesis extends beyond those individuals examined in a single study.

The distinction between independent groups and same subject designs is important since different statistical tests are used for hypothesis testing. In general, same subject research designs have more statistical power since there are fewer sources of variation in the experiment. Note that a randomized controlled trial (RCT), the golden standard of clinical trials, combines both design types by having pre and post measures for both a control and treatment group.

## Definition of null hypothesis: ..

So, you might get a *p*-value such as 0.03 (i.e., *p* = .03). This means that there is a 3% chance of finding a difference as large as (or larger than) the one in your study given that the null hypothesis is true. However, you want to know whether this is "statistically significant". Typically, if there was a 5% or less chance (5 times in 100 or less) that the difference in the mean exam performance between the two teaching methods (or whatever statistic you are using) is as different as observed given the null hypothesis is true, you would reject the null hypothesis and accept the alternative hypothesis. Alternately, if the chance was greater than 5% (5 times in 100 or more), you would fail to reject the null hypothesis and would not accept the alternative hypothesis. As such, in this example where *p* = .03, we would reject the null hypothesis and accept the alternative hypothesis. We reject it because at a significance level of 0.03 (i.e., less than a 5% chance), the result we obtained could happen too frequently for us to be confident that it was the two teaching methods that had an effect on exam performance.

## Journal of Articles in Support of the Null Hypothesis

The first step in hypothesis testing is to set a research hypothesis. In Sarah and Mike's study, the aim is to examine the effect that two different teaching methods – providing both lectures and seminar classes (Sarah), and providing lectures by themselves (Mike) – had on the performance of Sarah's 50 students and Mike's 50 students. More specifically, they want to determine whether performance is different between the two different teaching methods. Whilst Mike is skeptical about the effectiveness of seminars, Sarah clearly believes that giving seminars in addition to lectures helps her students do better than those in Mike's class. This leads to the following research hypothesis:

## Converting research questions to hypothesis is a simple task

By tradition, we try to disprove (reject) the null hypothesis. We can never prove a null hypothesis, because it is impossible to prove something does not exist. We can disprove something does not exist by finding an example of it. Therefore, in research we try to disprove the null hypothesis. When we do find that a relationship (or difference) exists then we reject the null and accept the alternative. If we do not find that a relationship (or difference) exists, we fail to reject the null hypothesis (and go with it). We never say we accept the null hypothesis because it is never possible to prove something does not exist. That is why we say that we failed to reject the null hypothesis, rather than we accepted it.

## 04/01/2018 · Do you know what a null hypothesis is

Null Hypothesis Research Hypothesis: Researcher’s expectation, prediction; also called hypothesis or alternative hypothesis

Null Hypothesis: No differences, no effects; differences or effects observed are the result of sampling error What you’re doing with statistics… Have a question/topic

Consult literature; create hypothesis (has an accompanying null hypothesis)

Sample a population and measure

Use statistics to estimate probability of your results being true to population; ruling out your null hypothesis to test the (research) hypothesis Significance Testing Test If you set your significance level at .05 and you get the following, significant or not?