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**Runs test** is a statistical test that is used to determine whether or not a dataset comes from a random process.

The null and alternative hypotheses of the test are as follows:

H_{0} (null): The data was produced in a random manner.

H_{a} (alternative): The data was *not *produced in a random manner.

This tutorial explains two methods you can use to perform Runs test in R. Note that both methods lead to the exam same results.

**Method 1: Run’s Test Using the ***snpar* Library

*snpar*Library

The first way you can perform Run’s test is with the **runs.test()** function from the **snpar **library, which uses the following syntax:

**runs.test(x, exact = FALSE, alternative = c(“two.sided”, “less”, “greater”))**

where:

**x:**A numeric vector of data values.**exact:**Indicates whether an exact p-value should be calculated. This is FALSE by default. If the number of runs is fairly small, you can change this to TRUE.**alternative:**Indicates the alternative hypothesis. The default is two.sided.

The following code shows how to perform Run’s test using this function in R:

library(snpar) #create dataset data #perform Run's test runs.test(data) Approximate runs rest data: data Runs = 5, p-value = 0.5023 alternative hypothesis: two.sided

The p-value of the test is **0.5023**. Since this is not less than α = .05, we fail to reject the null hypothesis. We have sufficient evidence to say that the data was produced in a random manner.

**Method 2: Run’s Test Using the ***randtests* Library

*randtests*Library

The second way you can perform Run’s test is with the **runs.test()** function from the **randtests **library, which uses the following syntax:

**runs.test(x, alternative = c(“two.sided”, “less”, “greater”))**

where:

**x:**A numeric vector of data values.**alternative:**Indicates the alternative hypothesis. The default is two.sided.

The following code shows how to perform Run’s test using this function in R:

library(randtests) #create dataset data #perform Run's test runs.test(data) Runs Test data: data statistic = -0.67082, runs = 5, n1 = 5, n2 = 5, n = 10, p-value = 0.5023 alternative hypothesis: nonrandomness

Once again the p-value of the test is **0.5023**. Since this is not less than α = .05, we fail to reject the null hypothesis. We have sufficient evidence to say that the data was produced in a random manner.