What is the principle of equally likely outcomes?

  • All outcomes are equally probable
  • All outcomes are identical
  • All outcomes are independent
  • All outcomes are mutually exclusive
The principle of equally likely outcomes is a basic assumption in the classical definition of probability. It states that if an experiment has n outcomes, and there's no reason to believe that any one outcome is more likely than any other, then each outcome is assumed to have an equal probability of 1/n. For example, in tossing a fair coin, heads and tails are equally likely.

________ clustering is a density-based clustering method that can find arbitrary shaped clusters and is less affected by outliers.

  • DBSCAN
  • Hierarchical
  • K-means
  • Spectral
DBSCAN (Density-Based Spatial Clustering of Applications with Noise) is a density-based clustering method that can find arbitrary shaped clusters and is less affected by outliers. It works based on the density of points in a region, growing clusters according to the density estimate.

What does the standard deviation measure in a dataset?

  • Central tendency
  • Dispersion
  • Kurtosis
  • Skewness
The standard deviation measures the amount of variation or dispersion in a set of values. A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the values are spread out over a wider range.

If the p-value from a Mann-Whitney U test is less than the significance level, you would ________ the null hypothesis.

  • accept
  • either accept or reject
  • fail to reject
  • reject
If the p-value from a Mann-Whitney U test is less than the significance level (often 0.05), you would reject the null hypothesis, suggesting there is a significant difference between the groups.

What does the Law of Large Numbers state?

  • It states that as the size of a sample is increased, the mean value of the sample will get closer to the mean or expected value of the population.
  • It states that if an event is repeated under identical conditions, the probability of the event remains the same.
  • It's a rule which states that the sum of the probabilities of all possible events is 1.
  • It's the law that states the probability of an event is always constant.
The Law of Large Numbers states that as a sample size grows, its mean gets closer to the average of the whole population. In other words, as the number of experiments increases, the actual ratio of outcomes will converge on the theoretical, or expected, ratio of outcomes.

The graphical representation of residuals versus predicted values is known as a ________ plot.

  • Box
  • Histogram
  • Residual
  • Scatter
A Residual plot is a graph that shows the residuals on the vertical axis and the independent variable on the horizontal axis. If the points in a residual plot are randomly dispersed around the horizontal axis, a linear regression model is appropriate for the data; otherwise, a non-linear model is more appropriate.

What can the Mann-Whitney U test tell you about the shape of your distributions?

  • It can confirm if your distributions are normal
  • It can confirm if your distributions are skewed
  • It can confirm if your distributions have equal variances
  • It cannot tell you anything about the shape of your distributions
The Mann-Whitney U test does not provide information about the shape of the distributions. It is a non-parametric test that does not make any assumptions about the distribution of the data.

What is the purpose of multiple linear regression analysis?

  • To classify data into different categories
  • To cluster data into different groups
  • To examine the relationship between several independent variables and a dependent variable
  • To predict the outcome of a binary dependent variable
Multiple linear regression analysis is used to understand the relationship between several independent (explanatory) variables and a dependent (response) variable. It can also be used for predicting the mean value of the dependent variable given the values of the independent variables.

What does a larger sample size do to the sampling distribution of the mean?

  • It decreases the spread of the distribution
  • It does not affect the distribution
  • It increases the spread of the distribution
  • It skews the distribution
A larger sample size decreases the spread of the sampling distribution of the mean. This is because as the sample size increases, the standard error (a measure of the spread of the distribution of sample means) decreases, which means that the sampling distribution becomes more concentrated around the true population mean.

What is the relationship between the eigenvalue of a component and the variance of that component in PCA?

  • It depends on the dataset
  • There is no relationship
  • They are directly proportional
  • They are inversely proportional
The eigenvalue of a component in PCA is directly proportional to the variance of that component. In other words, a larger eigenvalue corresponds to a larger amount of variance explained by that principal component.