When do we use a quasi-experiment?
When we cannot run a true experiment. If you do not have permission to randomly assign people to groups.
So, when we cannot run a field or lab experiment.
If you would study Netflix the same way as Datta, Knox, and Bronnenberg (2018), how would you set up the study?
Standard error of the coefficient
Measures how precisely the model estimates the coefficient’s unknown value.
The smaller the standard error, the more precise the estimate.
What can be concluded from a positive correlation?
That as the independent variable increases, the dependent variable also tends to increase.
p-value > significance level
p-value is higher than the significance level
It is not statistically significant. The influence of this independent variable could have been due to random chance.
There is insufficient evidence to conclude a relationship. We cannot reject the null hypothesis.
p-value < significance level
p-value is lower than the significance level
It is statistically significant.
There is enough/sufficient evidence that there is a relationship between the IV and the DV. We reject the null hypothesis.
What do the p-values indicate?
Whether the relationships are statistically significant.
If the relationship you observe in the sample also exists in the larger population.
What do coefficients describe?
The mathematical relationship between each independent variable (IV) and the dependent variable (DV).
Long-tail concept
A business strategy that allows companies to realise significant profits by selling low volumes of hard-to-find items to customers, instead of only selling low volumes of a reduced number of popular items.
Two factors that indirectly influence sales:
Consumer-brand usage (CBU)
Consumer-brand endorsement (CBE)
Propensity Score Matching
Quasi-experimental method in which the researcher uses techniques to construct an artificial control group by matching each treated unit with a non-treated unit of similar characteristics.
Difference supervised and unsupervised machine learning.
Supervised learning uses labeled input and output, while an unsupervised learning algorithm does not.
Unsupervised learning method
Machine learning algorithm that analyses and clusters unlabelled datasets.
These algorithms discover hidden patterns in data without the need for human intervention. Hence, they are unsupervised.
Supervised learning method
Machine learning approach that’s defined by its use of labeled datasets.
Using labelend inputs and outputs, the model can measure its accuracy and learn over time.
Machine learning methods can be subdivided into:
- Unsupervised methods
Gross Rating Point (GRP)
A ratio that measures the influence of advertising campaigns on their target audience.
Shapley Values Method
Method with which you are looking at comparable ‘paths to purchase’, with the difference being in that one channel is missing.
Limitations of PROSAD with respect to finding the impact a bid has on profitability.
What is PROSAD
A tool that investigates the effectiveness of Search Engine Advertising.
Problems occurring when measuring ROI based on clicks, sales, or visitor numbers instantly generated by a campaign.
They are useful, but rather seen as KPIs, and not as a measure of ROI.
What can be concluded from a positive correlation?
That as the independent variable increases, the dependent variable also tends to increase.
What can be concluded from a negative correlation?
That as the independent variable increases, the dependent variable decreases.
Interpreting r-squared
The larger the r-squared, the better the model explains the variations.
Higher r-squared: the more the dotted lines are closer to the regression model line.
Lower r-squared: the further away the dotted lines are from the regression model line.
What does the adjusted r-squared determine?
It determines how reliable the correlation is and how much it is determined by the addition of independent variables.