Consider the following hypothesis test:-

H₀: μ = 20

H₁: μ ≠ 20

A sample of 40 provided a sample mean of 19. The standard deviation is 3. Then the value of the t-test statistic is:

Which of the following is not a rejection rule for one sample t-test: (Where α is the level of significance)

(A) Reject null hypothesis $H_0$ : if $t \leq -t_\alpha$.

(B) Reject null hypothesis $H_0$ : if $t \geq -t_\alpha$.

(C) Reject null hypothesis $H_0$ : if $t \geq t_\alpha$.

(D) Reject null hypothesis $H_0$ : if $t \leq -t_{\alpha/2}$ or $t \geq t_{\alpha/2}$.

Choose the correct answer from the options given below:

Which of the following are correct?

(A) A statistical hypothesis is a statement about the population parameter which may be true or false.

(B) In a statistical hypothesis testing procedure, a Type I error is made when the null hypothesis is accepted when it is false.

(C) In a statistical hypothesis testing procedure, a Type II error is made when the null hypothesis is rejected when it is true.

(D) The number of degrees of freedom of a statistic is the number of independent variates used to compute that statistic.

Choose the correct answer from the options given below:

Tamanna was researching on problem of under-age workers at factories. She met a suitable child and interviewed him. He put her in contact with three another workers. Those three workers brought her in contact with ten other underage workers. This process of sampling is known as:

In a survey for a sample of 300 individuals, 180 persons gave responses 'Yes' and 100 gave responses 'No' and 20 gave "No response". Then point estimate of proposition in the population who responded "Yes" is

The following data are from a simple random sample: 3, 6, 8, 15, 5, 11. What is the point estimate of the population mean?

Consider the following hypothesis test.

$H_0: \mu \leq 12$

$H_a: \mu > 12$

If a sample of 25 is taken with sample mean 15 and a sample standard deviation of 6, then the value of t-test statistic is: