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How do you explain the P-value to a non-data person?

Say, how do you explain the P-value to your grandma?
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Let's say we have a fair coin and we toss the coin 50 times. What do we expect the results to be?

We expect to see around 25 Heads and 25 Tails in 50 tosses. But there is also some chance (no matter how little) that we might see 50 Heads and 0 Tails in 50 tosses of a fair coin.

P-value defines the probability (chance) of getting a result as extreme as 50 Heads and 0 Tails in 50 tosses of a fair coin.
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so lets say you test two different versions of UI

now say version A has better numbers compared to version B, now how confident can we be that versionA is superior to VersionB? --> this is where p - value comes in

P values are numbers between 0 and 1  that quantify how confident we can be that versioanA is different than versionB

closer p-value to zero --> more confident that both versions are different

in reality we use 0.05 as threshold 

 

so if p-value < 0.05 then statistically significant difference

if p>0.05 then statistically no difference

Note: p-value doesnt say the how much different versionA and versionB are, it just says that they are different

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Product description:

A P-value is a measure of the probability that an observed difference could have occurred just by random chance.

E.g., Revenue of Company varies which may be depend upon R&D Spend, Administration, Marketing spends, location etc.   

Significance-level (alpha-value): it is the percentage of risk while rejecting the Hypothesis.

If p-value

Objective: improve the Revenue of Company

Brainstorm ideas:

For improving the revenue of company, we will have to decide about the component on which revenue depends.

1.       I will define Significance-level (alpha -value) for the Experiment.

2.       I will build regression model using Revenue as Dependent variables and deciding component as independent variables.

3.      Run the experiment and check p-value of independent variables.

4.      If p-value>alpha-value, eliminate those independent variables.

5.      Again, run the experiment using revenue as Dependent variables and remaining as independent variables. Repeat step 2 to step 4 till we found all p-value

Hypothesis: Revenue of company doesn’t depend upon R&D Spend, Administration, Marketing Spend and location.    

Experiment:

1.       Define significance level (alpha-value)

2.      Build a linear regression model using variables R&D Spend, Administration, Marketing Spend and Location.

3.      Run the Model and check p-value of each variable.

Success Metrics:

1.      P-value of R&D spend

2.      P-value of Administration

3.      P-value of Marketing Spend

4.      P-value of Location

Trade-off:

1.      Although Low p-value promotes the rejection of the hypothesis, it addresses nothing about the probability of rejecting it.

2.      High p-value means that our data is highly consistent with our hypothesis, nothing more.

 

Once we have found the deciding variables about revenue, we can do A/B test on those variables for improving the revenue.  

 

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the question is to explain the concept to a non-data person..this answer does not explain in layman terms.

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