Category: Statistics

How To Determine Whether Something is a Trend
How do you know whether something is a trend or not? First, we need to define a trend. A trend is: a general direction in which something is developing or changing Second, we should mathematically define and be able to detect a trend. Trend analysis (and any kind of statistical analysis) is generally not something…

You Ask, I Answer: Marketing Trends vs. Tactics and Strategies?
Oleksandyr asks, “What defines a trend versus a tactic or a strategy?” Mathematically speaking, the definition of a trend is a sustained change in a metric over a period of time that can be proven with a statistical test. In the context of this question, I assume we’re talking about usage of particular channel, tactic,…

You Ask, I Answer: Causation Without Correlation?
Vito asks, “Let’s assume we have the joint probability distributions of A and B. In that scenario, is it possible that A causes B, but A and B are not correlated?” This is possible and even probable when you have missing data, especially if the missing data is also partially causal. Some examples: – Distributions…

You Ask, I Answer: Marketing Data Science Technical Skills?
Jessica asks, “When it comes to marketing data science, I’ve got very good business knowledge, but lack of the technical side. any advice?” The first question you have to ask is whether you need the handson skills or just knowledge of what’s possible. The second question is what skills you already have. Remember that in…

You Ask, I Answer: Determining Sample Sizes for Surveys?
Phil asks, “How do you determine a large enough sample size for things like our survey? I always thought 10% sample would be enough, but you seemed to think that’s not true?” It depends on the size of the overall population. The smaller the population, the larger the sample you need. It also depends on…

You Ask, I Answer: Hypothesis Formation Without Data Snooping in Marketing Data Science?
Jessica asks, “How would you differentiate hypothesis formation and searching for relevant variables WITHOUT “data snooping”?” Data snooping, or more commonly known as curve fitting or data dredging, is when you build a hypothesis to fit the data. The way to avoid this is by using evidence not included in the dataset you used to…

You Ask, I Answer: Sample Sizes for Web Analytics?
Courtney asks, “How many web sessions (or users) would you need to send to a website for the results to be significant?” At first, I thought this question was about A/B testing, which has a whole range of statistics for it. But Courtney is actually asking about how many visitors you need for web analytics…

You Ask, I Answer: Categorical Prediction Techniques for Google Analytics?
Maggie asks, “Would you use CHAID analysis to discover relationships between multiple categorical predictor variables? For example, using GA dimensions (traffic channel, device type, country, landing page, etc.) and group them according to their likelihood to convert. What else can be used for a similar analysis?” Maggie knows her stuff when it comes to statistics.…