# Null hypothesis: μ = 72 Alternative hypothesis: μ ≠72

An appropriate hypothesis/prediction from BIO 325L Write the prediction of the above.

AP Biology Lab 7 Name: _____ Genetics of Organisms Write a null hypothesis that describes the mode of inheritance of the trait you studied.

## Null hypothesis: μ = 72 Alternative hypothesis: μ ≠72

### Null hypotheses regarding the distribution of genetic variation.

The p-value is p = 0.236. This is not below the .05 standard, so we do not reject the null hypothesis. Thus it is possible that the true value of the population mean is 72. The 95% confidence interval suggests the mean could be anywhere between 67.78 and 73.06.

### What is a null hypothesis and how is it useful?

The **level of statistical significance** is often expressed as the so-called **p****-value**. Depending on the statistical test you have chosen, you will calculate a probability (i.e., the *p*-value) of observing your sample results (or more extreme) **given that the null hypothesis is true**. Another way of phrasing this is to consider the probability that a difference in a mean score (or other statistic) could have arisen based on the assumption that there really is no difference. Let us consider this statement with respect to our example where we are interested in the difference in mean exam performance between two different teaching methods. If there really is no difference between the two teaching methods in the population (i.e., given that the null hypothesis is true), how likely would it be to see a difference in the mean exam performance between the two teaching methods as large as (or larger than) that which has been observed in your sample?

## Choose the correct null and alternative hypotheses below A ..

where k is the number of comparison groups and N is the total number of observations in the analysis. If the null hypothesis is true, the between treatment variation (numerator) will not exceed the residual or error variation (denominator) and the F statistic will small. If the null hypothesis is false, then the F statistic will be large. The rejection region for the F test is always in the upper (right-hand) tail of the distribution as shown below.

## Null and Alternative Hypothesis | Real Statistics Using …

**Solution** First, we write write down the null and alternative hypothesesThis is a lefttailed test. The -score that corresponds to is . The critical region is the areathat lies to the left of . If thez-value is less than there we will reject thenull hypothesis and accept the alternative hypothesis. If it is greaterthan , we will fail to reject the nullhypothesis and say that the test was not statistically significant.Wehave There is another way to interpret the test statistic.