Reliability and Validity


Course Title


Reliability and Validity


In the broadest sense, reliability would be looking at the consistency of measurement. The feasibility is observed by measuring the variable several times. Thus, it would be able to prove if the measure is consistent enough (Kothari, 2014). Therefore, a measurement that would be higher is observed to be more reliable than one that would have lower scalability.

Inter-observer reliability is a measure utilizing statistics to address the issue of consistency as a form of measure. Test-retest reliability looks at the consistency level from one period to another (Kothari and Garg, 2014). Reliability can be internal (this would be tested occurring from variables within) or external (this would be tested occurring from outside variables).

Evaluation of interrater reliability would imply that the study uses the same collected results. Thus, the sample would imply a correlation amongst the various sets of variables that have been analyzed. Hence, when all the respondents give a similar value, the test would have higher interrater reliability (Kothari and Garg, 2014). Thus, the aspect of yielding similar results would prove that the test is of the essence and that it is scientific. Therefore, the inferences can be used in the decision-making process and improve the livelihoods of a people.

Test 1

Reliability Statistics

Cronbach’s Alpha N of Items

.066 2

Test 2

Reliability Statistics

Cronbach’s Alpha N of Items

.276 2

Thus, based on the analysis, test 2 is more reliable.

Thus, based on the scientific tools present and used to test for reliability, one would be able to come up with the best measure (Kothari and Garg, 2014). Thus, the repeated analysis would be able to give the best results of a given timeframe over the dataset.


Validity looks into what will be measured (Kothari and Garg, 2014). This would look at any types of errors that might arise in the questionnaire. For instance, would the variables make sense to the user of the information being used in place.

Internal validity looks at the inferences that carry out the observations amongst the variables to show the type of manipulation if it was done transparently or measured based on the study parameters (Kothari, 2014). External validity looks into the observations that are made based on the manipulation of several variables that would be extending outside.

Concerning the statistical conclusions that are present, the information user would be out to assess the type of analysis. This is whether the data they are getting and the questions they are asking are making sense (Kothari and Garg, 2014). Thus, it would be guided by a psychological framework tasked to improve the nature of analysis and data presentation.

Thus, the study would also have the required sample size. This depends on the statistical test that would be used to analyze the results (Kothari, 2014). Furthermore, the researcher would be keen to look into at least twenty percent of the total population from the total sample size.

For instance, a correlation coefficient at a significance level of 0.05 can be used to analyze. Thus, the result would be testing the significance and insignificance of the variable based on the present results (Kothari and Garg, 2014). Thus, data would form the basis of critique, and the scientists would be able to infer what is happening from the data available for the study.

Thus, the criteria for validity would be based on values 0 and 1.00. This is based on the connection size between the two variables under investigation. This would include variables a and b.


Test and measurement


A test and measurement would be used to analyze the strength of the variables based on numerical factors.

Psychometric Properties

It ought to be an accurate system and dependable based on the present analysis.

Psychometric Properties of the Instrument

This will be based on the reliability and validity factors inclined to the correlational coefficients (r = .41).


Kothari, C. R., & Garg, G. (2014). Research Methodology: Methods and Techniques. New Delhi:

New Age International Publishers.

Kothari, C. R. (2014). Research Methodology: Methods and Techniques (3rd ed.). New Delhi:

New Age International (P) Limited.