In the past few weeks people have been arguing on the social media forum https://www.reddit.com/r/ontario/ about whether the COVID-19 situation in Ontario was improving or getting worse.  Some users call those who focused on high spikes in new cases "doomers" (as in "ok doomer") such as the 460 new cases on Sunday May 24.  Recently the numbers of new cases have gone down to 287 on Tuesday the 26th and 292 for Wednesday the 27th.   Date # of New Cases 27-May 292 26-May 287 25-May 404 24-May 460 23-May 412 22-May 441 21-May 413   Data from https://data.ontario.ca/dataset/status-of-covid-19-cases-in-ontario, more easily-visible on https://news.google.com/covid19/map?hl=en-CA&gl=CA&ceid=CA%3Aen&mid=%2Fm%2F05kr_.   You will be answering the following questions about this data: What is the mean number of new cases of COVID-19 in Ontario over the 7 day period indicated? What is the standard deviation for these cases? What is the z-score for the data from May 26? What is the z-score for the data from May 24? Which of these two data values (the lowest value on May 26 or the highest value on May 24) represents the most significant difference from the recent average number of new cases?

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...