Basics of ML & AL Week 2 Challenge

1. Calculate All 4 Business Moments

1. Mean: Average of data.
2. Variance: Spread of data around the mean.
3. Skewness: Symmetry of data (positive or negative).
4. Kurtosis: "Peakedness" or tail heaviness of data.

2. Expected Value vs. Mean

Expected value is used in probability distributions for long-term averages, while the mean is a simple average of data points.

3. Is Skewness Bad in Analysis?

Not necessarily. Skewness just means the data isn't symmetric, which could require special statistical techniques.

4. Probabilities for Normal Distribution ($\mu = 680$μ=680, $\sigma = 31$σ=31)

a) $P(X < 711)$P(X<711): About 0.8413. b) $P(X > 740)$P(X>740): About 0.0268. c) $P(600 < X < 650)$P(600<X<650): About 0.1662. d) $P(X = 720)$P(X=720): 0 for any exact value in a continuous distribution.

5. Explain the Curve on the Right Side

The curve might be skewed:

• Right-skewed: Tail to the right (positive skew).
• Left-skewed: Tail to the left (negative skew).