by Jakob Staubmann
Economic, political, and media employers often promote the saying “numbers do not lie”, emphasizing the importance of accurate data and visual graphs in conveying information to the general public. However, it is crucial for non-specialists to delve deeper into the research behind these graphs and understand the methods used to build databases, analyze data, and the credibility of the sources and journalists involved.
In today’s rapidly evolving media landscape, data-driven and data-supported journalism has taken center stage. Journalists rely on visual representations of data to tell compelling stories and provide insights. However, it is essential to recognize that even with vast amounts of data, these visual representations can sometimes be misleading. Let’s explore some common tricks used in data presentation and interpretation.
The first trick involves percentages, particularly when comparing changes from one period to another. Often, only the percentage of change is highlighted without considering the actual numbers behind it. For example, a company may boast a 100% increase in sales this year compared to the previous year. However, if the actual numbers are small, such as selling 10 units in the first year and 20 units in the second year, the percentage increase may be misleading.
The second trick relates to “comparison without a uniform basis.” When comparing crime rates between two cities, it is essential to consider the population size. Comparing crime rates without accounting for population differences can lead to inaccurate conclusions. A higher crime rate in one city may simply be a reflection of its larger population.
The third trick involves the difference in comparison years. Institutions may choose specific years for comparison, often selecting the lowest year to highlight significant growth. However, comparing to other years may reveal a different picture. It is crucial to establish a disciplined and justified basis for comparing different years.
The fourth trick is related to “rounding.” Institutions may round numbers in a way that presents a more favorable image. Auditors and readers must pay attention to this practice to avoid being misled by rounded figures.
The fifth trick involves publishing data based on opinion polls without providing essential details such as the sample size, method of data collection, margin of error, and demographic representation. Without these details, the reliability of the poll results can be questionable. It is crucial to understand the circumstances under which the surveys were conducted.
The sixth trick revolves around comparing the results of opinion polls without considering the error coefficient. Neglecting the margin of error in both polls can render the results inaccurate.
The seventh trick is related to announcing growth results without clarifying the reasons and sources behind them. Companies may highlight significant profits without disclosing whether they are a result of regular operations, capital gains, or one-time events. Understanding the underlying factors behind these profits is essential to assess their sustainability.
The eighth trick involves recognizing that numbers usually represent a sample of society, rather than the entire population. When discussing average income or other statistics, it is crucial to acknowledge the limitations of the sample and its representativeness.
In conclusion, while numbers can be powerful tools for conveying information, it is essential to approach them with caution. Understanding the tricks behind data presentation and interpretation is crucial for non-specialists to avoid being misled. By delving deeper into the research behind graphs, questioning the sources, methods, and reasoning, we can develop a more informed perspective and make better judgments based on data. Remember, numbers may not lie, but it is the responsibility of journalists, auditors, and readers to ensure their accurate and transparent representation.