Share:

Knowledge Base

How to determine the sample size in statistics?

09/28/2023 | by Patrick Fischer, M.Sc., Founder & Data Scientist: FDS

Determining sample size in statistics depends on several factors, such as the desired confidence level, the expected standard deviation, the expected effect, and the desired precision of the estimate. There are several approaches to determining sample size, some of which I would like to introduce:

Confidence Level and Error Tolerance: determine the desired confidence level (usually 95% or 99%) and the maximum tolerance or precision you can accept for your estimate. These factors determine the width of the confidence interval around your estimate.

Standard deviation: estimate the standard deviation of the population or use estimates from previous studies. The standard deviation is a measure of the spread of the data around the mean.

Effect size: If you want to examine a specific effect size or difference between groups, you should use an estimate of the expected effect. For example, this could be the expected difference between the means of two groups.

Select the appropriate statistical test:Depending on the type of test (e.g., t-test, chi-square test) and the parameters you choose, use an appropriate formula to determine the sample size. These formulas are based on statistical assumptions and are specific to each test.

Determining sample size in statistics depends on several factors, such as the desired confidence level, expected standard deviation, expected effect, and desired

Use sample size calculation software: There are several online tools and software packages that can help you calculate sample size. These tools take into account the factors mentioned above and provide you with an estimate of the required sample size.

It is important to note that determining the sample size involves some uncertainty, as it is based on estimates and assumptions. It is often advisable to select a larger sample to ensure that the results are reliable and representative.

Like (0)
Comment

What is the concept of p-value and how is it interpreted?

09/28/2023 | by Patrick Fischer, M.Sc., Founder & Data Scientist: FDS

The concept of the p-value is a statistical method used in hypothesis testing to assess the strength of evidence against a null hypothesis. The p-value indicates how likely the observed data is, or an even more extreme observation, given the null hypothesis.

Here is the general flow of interpreting a p-value:

Formulation of the null hypothesis (H₀) and the alternative hypothesis (H₁): The null hypothesis is the assumption that there is no effect or relationship between the variables examined. The alternative hypothesis states that an effect or relationship exists.

Perform statistical analysis: Data is collected and an appropriate statistical test method is applied to calculate the p-value.

P-value interpretation: The p-value ranges from 0 to 1. A typical threshold for significance is 0.05. If the p-value is less than 0.05, it is often considered statistically significant and the null hypothesis is rejected in favor of the alternative hypothesis. A small p-value indicates that the observed data would be unlikely if the null hypothesis were true.

Be careful with interpretation: A significant p-value does not automatically mean that an effect is practically important. It just means that if the null hypothesis is true, the probability of getting the observed data is relatively small. The practical meaning of the effect should always be considered in conjunction with the p-value and other statistical measures.

It is important to note that the p-value alone does not predict whether an alternative to the null hypothesis is true or false. It only indicates how strongly the available data speak against the null hypothesis. Therefore, interpreting a p-value requires some statistical knowledge and understanding of context.

Like (0)
Comment

What does classic press relations involve?

09/28/2023 | by Patrick Fischer, M.Sc., Founder & Data Scientist: FDS

Classical public relations, also referred to as "public relations" (PR), encompasses a range of activities and strategies aimed at obtaining positive media coverage about a company, organisation or individual. The main objectives of classical public relations are to create public awareness, build and maintain a positive image and disseminate information to the target audience. Here are some of the most important aspects of classical press relations:

Press releases: The creation and distribution of press releases to share recent news, developments or announcements. Press releases are designed to encourage journalists to cover the company or organisation.

Media contacts: Cultivating relationships with journalists, editors and other media representatives. This includes identifying relevant contacts in the media and communicating with them to encourage potential coverage.

Press conferences: The organisation of press conferences or media events to present important announcements or events to the public and the media.

Media relations: The proactive approaching of journalists and media representatives to offer story ideas or background information and encourage them to report on the company or organisation.

Crisis communication: Handling PR crises when negative information or issues arise to minimise damage to image and keep the public informed.

Tracking media coverage: Monitoring media sources to find out what stories are being published about the company or organisation and how they are perceived.

Demonstrating expertise: Positioning company representatives or experts as sources of expertise in the media to enhance reputation and credibility.

Media materials: The creation and provision of materials such as background information, images and videos to assist journalists in their reporting.

Relationship management: The ongoing cultivation of relationships with media representatives and other stakeholders to ensure long-term PR success.

Classical press relations is an important part of the communication strategy of companies, non-profit organisations, governments and other institutions. It helps shape and maintain an organisation's image and reputation, and influence public opinion and perception. In today's digital era, classic press relations can also be complemented online and in social media to reach a broader audience.

Like (0)
Comment

What role does storytelling play in PR?

09/27/2023 | by Patrick Fischer, M.Sc., Founder & Data Scientist: FDS

Storytelling plays a crucial role in public relations (PR). It is an effective way to convey messages, attract attention, and create an emotional connection with target audiences. By using stories, PR professionals can simplify complex information, illustrate the value and relevance of their organization or brand, and capture the public's interest.

Here are some important roles that storytelling plays in PR:

Get attention: By telling compelling stories, PR professionals can capture the attention of the media, target audiences and other stakeholders. A well-told story has the potential to stand out from other news stories and generate interest

Make an emotional connection: Stories have the ability to stir emotions and create a deeper connection with people. By telling stories that reflect their organization's or brand's values, vision or experience, PR professionals can build an emotional connection and gain the trust of their target audiences.

Communicating complex information: Often the messages and information to be communicated in PR are complex and difficult to understand. Storytelling allows this information to be put into a narratively engaging form that is more accessible and understandable. The use of stories can illustrate abstract concepts and promote understanding.

Build credibility and authenticity: By telling stories, PR professionals can build credibility and authenticity for their organization or brand. Stories based on real experiences and successes convey a sense of authenticity and build trust with target audiences.

Influence media coverage: Journalists and media outlets are often looking for compelling stories that engage their audiences. By telling compelling stories, PR professionals can pique the media's interest and increase their chances of receiving positive coverage.

Overall, storytelling in PR plays a pivotal role in conveying complex information in an understandable way, capturing the interest of target audiences, creating emotional connections and building trust in an organization or brand. Through the power of stories, PR professionals can communicate their messages more effectively and build long-term relationships with target audiences.

Like (0)
Comment

What is the concept of autocorrelation and how is it measured?

09/27/2023 | by Patrick Fischer, M.Sc., Founder & Data Scientist: FDS

Autocorrelation is a statistical concept that describes the relationship between the values ​​of a time series and their time-shifted values. It measures the magnitude and strength of dependencies or patterns in the data over time.

Autocorrelation is typically measured as a correlation coefficient, which indicates how strongly the values ​​in a time series correlate with each other. The correlation coefficient can assume values ​​between -1 and 1. A value of 1 indicates perfect positive autocorrelation, i.e. as one value increases in the time series, the offset values ​​also increase. A value of -1 indicates perfect negative autocorrelation, i.e. as one value increases in the time series, the offset values ​​decrease. A value of 0 indicates no autocorrelation, i.e. there is no linear relationship between the values ​​and their offset values.

There are several methods of measuring autocorrelation. A commonly used method is to calculate the correlation coefficient using the correlation function, e.g. the Pearson correlation coefficient. This coefficient indicates how strong the linear relationship is between the values ​​of a time series and their offset values.

The autocorrelation can also be represented graphically, e.g. by an autocorrelation diagram or a so-called correlogram. The correlation coefficient for various time shifts is displayed in a correlogram, which allows patterns or periodic dependencies in the data to be made visible.

Autocorrelation is an important concept in time series analysis and is used in various fields such as economics, finance, signal processing, and climate research to explore dependencies and patterns in temporal data.

Like (0)
Comment

Our offer to you:

Media & PR Database 2024

Only for a short time at a special price: The media and PR database with 2024 with information on more than 21,000 newspaper, magazine and radio editorial offices and much more.

Newsletter

Subscribe to our newsletter and receive the latest news & information on promotions: