_________ is a condition in which the error term in a regression model is correlated with itself.
- Autocorrelation
- Homoscedasticity
- Multicollinearity
- Underfitting
Autocorrelation, also known as serial correlation, is the correlation of a signal with a delayed copy of itself as a function of delay. In the context of a regression analysis, it refers to the condition when the error term (residuals) in a regression model is correlated with itself.
What is the value of the probability of an impossible event?
- 0
- 0.5
- 1
- The probability is undefined
By definition, the probability of an impossible event is 0. This is because the measure of probability assigns 0 to events that cannot occur and 1 to events that are certain to occur.
How does the effect size relate to the power of a t-test?
- Effect size has no relation to the power of a test
- Larger effect sizes are associated with higher power
- Larger effect sizes are associated with lower power
- nan
The effect size is the magnitude of the difference between groups. Larger effect sizes are easier to detect and are associated with higher power in a t-test.
How can one adjust for multicollinearity in a multiple linear regression model?
- By adding interaction terms
- By increasing the sample size
- By removing one of the correlated variables or combining the correlated variables
- By transforming the dependent variable
To adjust for multicollinearity in a multiple linear regression model, one of the common strategies is to remove one of the highly correlated independent variables or to combine the correlated variables.
The distribution of the sample mean will approach a normal distribution as the sample size increases, according to the _________.
- Central Limit Theorem
- Law of Large Numbers
- Probability Rule
- Sampling Distribution
According to the Central Limit Theorem, the distribution of the sample mean will approach a normal distribution as the sample size increases. Regardless of the shape of the population, the distribution of sample means taken with large enough sample size can be approximated by a normal distribution.
In a box plot, the 'box' represents the ________ quartile range of the data.
- Full
- Inter
- Lower
- Upper
The 'box' in a box plot represents the interquartile range (IQR) of the data. This is the range within which the middle 50% of the data falls, calculated as the difference between the third quartile (Q3) and the first quartile (Q1).
How is the test statistic computed in the Sign Test?
- By averaging the ranks
- By counting the number of positive and negative signs
- By summing the differences
- By summing the ranks
In the Sign Test, the test statistic is computed by counting the number of positive and negative signs of the differences between paired observations.
In simple linear regression, the assumption that the variance of the errors is constant across all levels of the independent variables is known as ________.
- autocorrelation
- heteroscedasticity
- homoscedasticity
- multicollinearity
In statistics, homoscedasticity (or homoskedasticity) is the assumption that the variance of the errors is constant across all levels of the independent variables. This is an important assumption in regression models, including simple linear regression.
How does sample size affect the accuracy of a statistic?
- Larger samples lead to less accurate statistics
- Larger samples lead to more accurate statistics
- Sample size does not affect the accuracy of a statistic
- The relationship between sample size and statistic accuracy is unpredictable
Larger samples tend to lead to more accurate statistics. The reason is that as we increase the sample size, the sample mean gets closer to the population mean, reducing the standard error. In other words, larger samples provide a better estimate of the population parameters, leading to more accurate and reliable results. However, this doesn't mean larger samples are always feasible or more effective, as they require more resources and time.
To redirect the response to another resource, the __________ method is used in servlets.
- forward()
- forwardResponse()
- redirect()
- sendRedirect()
The sendRedirect() method is used to redirect the response to another resource in servlets.
Which method is used to read form data sent via POST request in a servlet?
- request.getFormData()
- request.getParameter()
- request.readParameter()
- request.readPostData()
The request.readPostData() method is used to read form data sent via POST request in a servlet.
What is primarily stored in ServletConfig?
- Context attributes
- Request parameters
- Servlet parameters
- Session data
ServletConfig primarily stores servlet parameters, which are initialization parameters for a servlet.