inference_steps - the Department of Statistics Online Learning!
... However, since the t-distribution is symmetric P(T < -1.89) is the same as P(T > 1.89). This is why we use P(T > absolute value of the t-test statistic) when using the table. The degrees of freedom (df) for this test is equal to the sample size minus one, or 215. Since the T-table does not have 215 ...
... However, since the t-distribution is symmetric P(T < -1.89) is the same as P(T > 1.89). This is why we use P(T > absolute value of the t-test statistic) when using the table. The degrees of freedom (df) for this test is equal to the sample size minus one, or 215. Since the T-table does not have 215 ...
1. The average monthly electric bill of a random sample of 256
... a. What is the probability that the sample mean will be larger than 1224? b. What is the probability that the sample mean will be less than 1230? c. What is the probability that the sample mean will be between 1200 and 1214? d. What is the probability that the sample mean will be greater than 1200? ...
... a. What is the probability that the sample mean will be larger than 1224? b. What is the probability that the sample mean will be less than 1230? c. What is the probability that the sample mean will be between 1200 and 1214? d. What is the probability that the sample mean will be greater than 1200? ...
chapter3
... Range = Max. value – Min. value - the difference between the largest and smallest observations. Two data sets may have the same mean but different ranges. The Sample Standard Deviation – measures variation - tells how far, on average, the observations are from the mean - like the mean, it is not a r ...
... Range = Max. value – Min. value - the difference between the largest and smallest observations. Two data sets may have the same mean but different ranges. The Sample Standard Deviation – measures variation - tells how far, on average, the observations are from the mean - like the mean, it is not a r ...
Confidence Intervals
... For example, a final poll on the day before an election would want the margin of error to be quite small (with a high level of confidence) in order to be able to predict the election results with the most precision. This is particularly relevant when it is a close race between the candidates. The ...
... For example, a final poll on the day before an election would want the margin of error to be quite small (with a high level of confidence) in order to be able to predict the election results with the most precision. This is particularly relevant when it is a close race between the candidates. The ...
Chapter 5: The standard deviation as a ruler and the normal model
... Chapter 5: The standard deviation as a ruler and the normal model p131 Which is the better exam score? − 67 on an exam with mean 50 and SD 10 − 62 on an exam with mean 40 and SD 12? Is it fair to say: − 67 is better because 67 > 62? − 62 is better because it is 22 marks above the mean and 67 is only ...
... Chapter 5: The standard deviation as a ruler and the normal model p131 Which is the better exam score? − 67 on an exam with mean 50 and SD 10 − 62 on an exam with mean 40 and SD 12? Is it fair to say: − 67 is better because 67 > 62? − 62 is better because it is 22 marks above the mean and 67 is only ...
ExtraExercise from the book - Center for Statistical Sciences
... unable to reject H o at the 0.01 level of significance. We do not have any evidence thm mean arterial blood pressure differs for the two populations of women. b. To begin, we can approximate the t distribution with 45 df by the t distribution with 40 df. In this case, 99% of the observations are enc ...
... unable to reject H o at the 0.01 level of significance. We do not have any evidence thm mean arterial blood pressure differs for the two populations of women. b. To begin, we can approximate the t distribution with 45 df by the t distribution with 40 df. In this case, 99% of the observations are enc ...