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