When we don't have access to population variance, we get an estimate of the sample variance by [ Select ] ["dividing one from the sample size", "adding one to the sample size", "subtracting one from the sample size"] . This is known as [ Select ] ["unbiased sample variance", "corrected formula"] . This formula controls for some of the [ Select ] ["bias", "inflation"] and gets us closer to the actual population variance.

One of the following is an example of a question that might be asked to ascertain a problem with a nonrepresentative sample. Which one? O Do the signs of the residuals alternate? O Does the population have an omitted variable? O Do the residuals show nonconstant variance? O Does the sample contain about the same geographic coverage as the population?

Find the variance from the following sample. (Please round your answers to two decimal places, ex: 1.23)  +-----------------------------------+  |       X:    2    2    3    5    6 |

Find the variance from the following sample. (Please round your answers to two decimal places, ex: 1.23)  +---------------------------------------------+  |  X:   32   33   33   34   34   34   35 |

Consider the following problem where we work for an oil company that looks for oil in geographic formations that are favorable to the formation of oil. Find the expected value for barrels of oil in problem A and then find the variance and standard deviation. For B, find the mean, variance, and standard deviation using formulas. For variance and standard deviation, use the population formulas. Compare A and B, and what do you observe? Problem A                          Problem B Problem. A Oil (barrel)   Odds   Problem. B    Oil (barrel) ·           Odds 2 25% ·         2 ·         25% 4 25% ·         4 ·         25% 4 25% ·         4 ·         25% 2 25% ·         6 ·         25%

1. When applying one-way analysis of variance (ANOVA), all the following are key assumptions that should be satisfied EXCEPT: A. Samples are obtained independently and randomly from the population defined by the factor level. B. The mean of the samples taken from the population is always equal. C. The population at each factor level is approximately normally distributed. D. The population have a common variance. 4. The sum of squares for treatment (SST) measures: A. the variation above the k sample means. B. the variation below the k sample means. C. the variation between the k sample means. D. the variation within the k sample means. 5. Which of the following is NOT true for the F- distribution? A. It is generally skewed to the left. B. It has two degrees of freedom. C. It is continuous. D. Its units are non-negative. 2. Which of the following components in an ANOVA table are NOT additive? A. Mean squares B. Degree of freedom C. Sum of squares D. It is not possible to tell. 3. The…

In a survey, each participant indicated how much they agreed with the statement, "Hard work is the way to get what you want in life." Which of the following would you expect to have zero correlation, or close to zero correlation, with the response to the above statement? A) Agreement with the statement, "Happiness mostly depends on luck."   B) Conscientiousness score on a personality inventory test.   C) High school GPA.   D) A random number between 0 and 10, chosen by the participant.

Which of the following is not one of the assumptions made in the analysis of variance? O A. None of these O B. The different populations all have the same mean. O C. The different populations all have the same standard deviation o O D. The distribution of the response variable is a normal. O E. Each sample is an independent random sample.