Correlational and causal research both follow similar basic
scientific research design, where a research question is posed, then followed
with a hypothesis and a null-hypothesis, where quantitative data either supports
the research or null hypothesis
The relationship between age and driving speed
Does the example demonstrate a causal or correlational relationship?
The above example attempts to demonstrate a correlational
relationship due to several reasons. The first is that it is vaguely phrased
What’s needed to demonstrate a causal relationship?
The main requirement for demonstrating a causal relationship is to
account for extraneous or confounding variables. Such variables are third party
variables that aren’t accounted for and might influence the relationship
between the variables being studied (age and driving speed)
Evaluate whether a chi-squared test or a correlation coefficient would be more suitable to analyze the data in the example.
In order to properly analyze the data in the example, it is important identify the variable types, which will aid in identifying the most suitable test type. Chi-squared test, an association test, is used to demonstrate that the phenomena co-occur among two or more nominal variables (Dancey & Reidy, 2017). Therefore, if the example was phrased as such: how is gender (nominal) associated with driving speed (nominal), then Chi-squared would be most suitable.
Moreover, how the data is collected can sway the researcher to
choose one of two types of correlation coefficients in order to evaluate the
data. If an ordinal scale was used to collect the data, a non-parametric, is in
does not rely of a normal distribution, test called Spearman’s rank order
correlation would be the likely option
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Dancey, C., & Reidy, J. (2017). Hypothesis testing and statistical significance . In Statistics Without Maths for Psychology (7th ed.) (pp. 134-173). Harlow, UK: Pearson.
Dancey, C., & Reidy, J. (2017). Non-parametric statistics . In Statistics Without Math for Psychology (7th ed) (pp. 516-550). Harlow, UK: Pearson.
Gonzalez, K. (2018). What is a null hypothesis? - definition & examples. Retrieved 7 19, 2018, from Study: https://study.com/academy/lesson/what-is-a-null-hypothesis-definition-examples.html
Huff, D. (1973). How to lie with statistics. London: Penguin.
Schmid, F., & Schmidt, R. (2007). Multivariate extensions of Spearman's rho and related statistics. Statistics & Probability Letters, 407-416.
SEP. (2016). Correlational research. Salem Encyclopedia Press, Retrieved from https://liverpool.idm.oclc.org/login?url=https://search.ebscohost.com/login.aspx?direct=true&db=ers&AN=119214045&site=eds-live&scope=site.
Srinagesh, K. (2006). Planning the experiments in statistical terms. In The Principles of Experimental Research (pp. 333-372). Amsterdam : Butterworth Heinmann.