Question

a. Why is a random sample typically not collected? Develop a research question and determine how we would need to organize the study to use random sampling.

b. Imagine that you flip a coin 50 times. How would you use the terms trial, outcome, and success to describe this task?

c. What is the difference between the null hypothesis and the research, or alternative, hypothesis? Why do we never accept the null hypothesis or the research hypothesis?

d. What are Type I and Type II errors, and why are Type I errors considered to be particularly detrimental to research?

Answer 1

A) random sample is the sample drawn from the population will all the individuals having equal probability of getting selected. But in order to do that we need entire population at hand and this task in itself is quite difficult. Further if it is available then sampling randomly is almost impossible and every possible method that we can design has some bias or preference for some individuals.

B) the number of tosses which are 50 are called as trials.

The result that would come up on each toss is called the outcome

Success is defined as the number of heads that appear in the 50 trials.

C) Null hypothesis is the hypothesis which is assumed to be true. It is which has not much influence if it got changed. It is general acceptance which is believed by individuals.

Research or alternate hypothesis is the hypothesis which defines the deviation from the original accepted hypothesis.

The hypothesis are never accepted because we need to establish the truth by testing the hypothesis.

D) type 1 error is the probability of rejecting null hypothesis when it is true.

Type 2 error is probability of accepting null hypothesis when it is false.

Type 1 error is more important as it deals with the rejection of true null hypothesis. That is true general belief. Changing the general accepted belief is more risky.