## 1. What does a p-value in hypothesis testing indicate?

### Answer:

### Explanation:

The p-value represents the probability of obtaining results at least as extreme as the observed results, under the assumption that the null hypothesis is true.

## 2. What is the median in statistics?

### Answer:

### Explanation:

The median is the value separating the higher half from the lower half of a data sample, arranged in ascending order.

## 3. What is a type I error in hypothesis testing?

### Answer:

### Explanation:

A type I error occurs when the null hypothesis is incorrectly rejected, also known as a "false positive."

## 4. What is the range in statistics?

### Answer:

### Explanation:

The range is a measure of dispersion, defined as the difference between the largest and smallest values in a dataset.

## 5. What is a scatter plot used for?

### Answer:

### Explanation:

A scatter plot is used to determine the relationship or association between two quantitative variables.

## 6. What is the standard deviation?

### Answer:

### Explanation:

Standard deviation is a measure of the amount of variation or dispersion of a set of values, defined as the square root of the variance.

## 7. What does the null hypothesis typically state in hypothesis testing?

### Answer:

### Explanation:

The null hypothesis usually states that there is no effect or no significant difference, and it is the hypothesis that the study aims to test against.

## 8. What is a histogram used for?

### Answer:

### Explanation:

A histogram is a graphical representation showing the distribution of a single quantitative variable by dividing it into bins and counting the frequency of observations in each bin.

## 9. What does correlation measure?

### Answer:

### Explanation:

Correlation measures the strength and direction of a linear relationship between two variables, but it does not imply causation.

## 10. What is a confidence interval?

### Answer:

### Explanation:

A confidence interval is a range of values, derived from the sample statistics, that is likely to contain the value of an unknown population parameter.

## 11. What is the mode in statistics?

### Answer:

### Explanation:

The mode is the value that appears most frequently in a data set.

## 12. What is a categorical variable?

### Answer:

### Explanation:

A categorical variable is a type of variable that can take on one of a limited and usually fixed number of possible values, assigning each individual or other unit of observation to a particular group or nominal category.

## 13. What is a z-score?

### Answer:

### Explanation:

A z-score is a statistical measurement that describes a value's relationship to the mean of a group of values, measured in terms of standard deviations from the mean.

## 14. What is the central limit theorem?

### Answer:

### Explanation:

The central limit theorem states that the distribution of sample means approximates a normal distribution (regardless of the population distribution) as the sample size gets larger, provided the sample size is sufficiently large.

## 15. What is inferential statistics?

### Answer:

### Explanation:

Inferential statistics involves using data from a sample to make inferences about a population. It includes estimating population parameters, hypothesis testing, etc.

## 16. What does the term 'bi-modal' refer to in statistics?

### Answer:

### Explanation:

A bi-modal distribution is one that has two different modes or peaks. These distributions can show that the data has two different populations.

## 17. What is the purpose of a box plot in statistics?

### Answer:

### Explanation:

A box plot is a standardized way of displaying the distribution of data based on a five-number summary: minimum, first quartile (Q1), median, third quartile (Q3), and maximum. It is useful for showing the spread and skewness in a dataset.

## 18. What is a linear regression used for?

### Answer:

### Explanation:

Linear regression is used to model the relationship between a dependent variable and one or more independent variables by fitting a linear equation to observed data.

## 19. What is the coefficient of determination (R-squared) in linear regression?

### Answer:

### Explanation:

The coefficient of determination, denoted R-squared, is a key output of regression analysis. It is interpreted as the proportion of the variance in the dependent variable that is predictable from the independent variables.

## 20. What is a probability distribution?

### Answer:

### Explanation:

A probability distribution is a statistical function that describes all the possible values and likelihoods that a random variable can take within a given range.

## 21. What does an outlier in a dataset represent?

### Answer:

### Explanation:

An outlier is an observation that lies an abnormal distance from other values in a random sample from a population, often indicating either variability in the measurement or an experimental error.

## 22. What is a sampling distribution?

### Answer:

### Explanation:

A sampling distribution is a probability distribution of a statistic obtained through a large number of samples drawn from a specific population.

## 23. What is the purpose of a control group in experimental design?

### Answer:

### Explanation:

A control group in an experimental design is used as a baseline to compare groups and assess the effect of that treatment.

## 24. What is a non-parametric test in statistics?

### Answer:

### Explanation:

Non-parametric tests are statistical tests that do not assume a specific distribution for the data. They are used when the assumptions of parametric tests are not met.

## 25. What is the interquartile range (IQR) in statistics?

### Answer:

### Explanation:

The interquartile range (IQR) is a measure of statistical dispersion and is the range between the first quartile (25th percentile) and the third quartile (75th percentile).