Unlocking the Power of Sample Size: Enhancing Science Literacy and Media Evaluation

Empowering Individuals to Navigate Everyday Information and Media Bias

Every once in a while, I notice that someone I know has a big misunderstanding about sample size in the media.

One example is when people say that they believe that vaccines cause autism. Usually, they have read one or two articles by someone who has the same beliefs and have ignored the many highly credible research articles that concluded that there is no connection.

It would not be that hard to teach people about the importance of sample size, and yet, I don’t hear much about it being discussed outside of university statistics classes and graduate schools.

The three principles of sample size everyone should know:

The determination of sample size in statistics is crucial for ensuring that the data collected is representative and capable of providing reliable estimates or inferences about the population from which it is drawn.

Here are some basic principles underlying sample size determination in statistics:

Accuracy and Precision: The sample size should be chosen to ensure that the estimates derived from the sample closely approximate the true population parameters with a desired level of accuracy and precision.

For example, if a political survey is being conducted to determine who is likely to be elected president of the United States, the researchers should choose enough people who are representative of all voters to come up with accurate estimates.

Sometimes it takes experience to determine how many people are required and how they should be elected.

For example, a criticism I have heard from people who want to discredit survey results is that the “sample size was too small to accurately represent a large population,” such as the United States.

If one wanted to discredit the Nielsen TV ratings, one could point out the small sample size. However, Nielsen has had many years to perfect their technique. As of January 2022, Nielsen sampled about 40,000 households to represent all households in the United States.

Population Variability: The variability or dispersion within the population affects the required sample size. More variability typically requires a larger sample size to achieve the desired level of precision.

Marketers realize that people often differ in their purchasing behavior, depending on what neighborhood, state, and region of the country they live in.

Because of this knowledge, market research companies have collected consumer information in different areas of the country, known as geodemographic research.

Claritas PRIZM Premier is a set of geo-demographic segments for the United States, developed by Claritas Inc., which was owned under The Nielsen Company umbrella from 2009 to 2016.

One example of a market segment described by PRIZM is the Young Digerati: This group is choosing to start families in fashionable neighborhoods on the urban fringe. They are highly educated and very tech-savvy. These areas are typically in or near city centers of major metropolitan areas and are known for their vibrant cultural scenes, diverse dining options, and access to entertainment and nightlife.

Population Size: In some cases, particularly when dealing with finite populations, the size of the population being sampled can influence the sample size calculation. When the population is large relative to the sample size (usually over 10,000), adjustments may be necessary, but the entire population may be feasible to sample for smaller populations.

Implications for better media literacy:

One thing that many Americans need, especially young people, is better media literacy.

Media literacy refers to the ability to access, analyze, evaluate, and create media in a variety of forms, including print, digital, and multimedia. It involves understanding how media messages are constructed, as well as the impact and influence they have on individuals and society.

Media literacy also encompasses critical thinking skills that enable people to interpret media content accurately, recognize biases and stereotypes, and make informed decisions about the media they consume.

I remember, many years ago, when a student told me that he didn’t like statistics because they were used to lie and mislead the recipient of the information.

I responded that sometimes that happens, but when you understand sample size and statistics, you are better able to assess when statistics are being used to lie and mislead.

This empowers people to critically evaluate the credibility of media reports and identify instances where statistics are misused to support a particular agenda or narrative.

Evaluating News Coverage: In today’s digital age, individuals are inundated with news from various sources, including traditional media outlets, social media, and online platforms. Statistical literacy enables individuals to assess the quality and reliability of news coverage.

Sample size can also apply to the number of sources one uses to verify that a piece of information is correct.

For example, I have a cousin who is intelligent but never went to college. She is a very dedicated and outspoken Christian Conservative. I told her one time how I used research principles that I learned in my Ph.D. program to determine the reliability and validity of information in the news.

I asked what method she used. Interestingly, she said that she chose information that God would approve of. I’m assuming that meant information that supports the Christian Conservative agenda.

I could see by looking at her Facebook posts that they were mostly from popular conservative sources, such as Fox News. My cousin rarely checked more than one source of information, and they were certainly not from any left-wing publications.

This cousin also seemed to have no idea how to check the credibility of her sources of information.

Media-literate citizens are not as easy to take advantage of

Many individuals and organizations publish biased, misleading, and untruthful information.

Empowering individuals with sample size and statistical literacy not only fosters a more informed citizenry but also cultivates a society where misinformation and manipulation are met with skepticism and critical inquiry.

By advocating for widespread education on sample size and statistical literacy, we can fortify society against the pitfalls of media bias and misinformation, ultimately fostering a more informed and discerning public.