The hypothesis being tested is called the and is denoted H0.

Before actually conducting a hypothesis test, you have to put two possible hypotheses on the table — the null hypothesis is one of them. But, if the null hypothesis is rejected (that is, there was sufficient evidence against it), what’s your alternative going to be? Actually, three possibilities exist for the second (or alternative) hypothesis, denoted Ha. Here they are, along with their shorthand notations in the context of the pie example:

The standard deviation of  , if the null hypotheses is true (i.e., when o = 0.5) is:

How do you know which hypothesis to put in H0 and which one to put in Ha? Typically, the null hypothesis says that nothing new is happening; the previous result is the same now as it was before, or the groups have the same average (their difference is equal to zero). In general, you assume that people’s claims are true until proven otherwise. So the question becomes: Can you prove otherwise? In other words, can you show sufficient evidence to reject H0?


How to Set Up a Hypothesis Test: Null versus Alternative

Finally, say you work for the company marketing the pie, and you think the pie can be made in less than five minutes (and could be marketed by the company as such). The less-than alternative is the one you want, and your two hypotheses would be


What are Null hypothesis and alternative hypothesis

Hypothesis testing for proportions is similar to hypothesistesting for the mean (Section 7.2). Recall from section 6.3 that the mean andthe standard error of the mean for the proportion are:

Synonyms for Alternative hypothesis in Free Thesaurus

When a study is being planned, it is possible to choose the sample size to set the power to any desired value for some particular alternative to the null hypothesis.

Antonyms for Alternative hypothesis

Determine the standardized test statistic. Note that this is the sample mean minus the hypothesized mean over the standard error of the mean.

About “The Alternative Hypothesis”

An equivalent way of deciding whether to accept or reject theNull Hypothesis is to determine whether the standardized test statistic fallswithin a range of values called the rejection region of the samplingdistribution (p 339).

Hypothesis testing and p-values (video) | Khan Academy

Remember theP-value is the probability of getting a result as extreme as you obtainedand the level of significance is the maximum allowable probability of making aType I error (rejecting the null hypothesis when it is actually true). The decisionrule based on the P-Value is: compare the P-value to , then (p 334)

What is the difference between the null hypothesis and …

On the other hand, the null hypothesis is straightforward -- what is the probability that our treated and untreated samples are from the same population (that the treatment or predictor has no effect)? There is only one set of statistical probabilities -- calculation of chance effects. Instead of directly testing H, we test H. If we can reject H, (and factors are under control), we can accept H. To put it another way, the fate of the research hypothesis depends upon what happens to H.