Stats Study Sheet

We conduct an independent sample t-test using Excel, and obtain the following output (see t-test-height)

2) Compute the standard deviation for each of the four samples. Does the assumption of .21 for the population standard deviation appear reasonable?

(21) You took a sample of size 21 from a normal distribution with a known standard deviation, . In order to find a 90% confidence interval for the mean, You need to find.

5. Give the standard deviation for the mean and median column. Compare these and be sure to identify which has the least variability?

Let’s assume you have taken 1000 samples of size 64 each from a normally distributed population. Calculate the standard deviation of the sample means if the population’s variance is 49.

Standard Deviation for the mean column is 0.476Standard Deviation for the median column is 0.754Standard deviation for the mean column has least variability

Oftentimes students focus on their studies from Sunday through Thursday but as the weekend approaches, their attention shifts from academics to partying. The fact that the majority of their alcohol consumption is over a three day period (Thursday, Friday, Saturday) could be considered binge drinking. Binge drinking is defined as having four to five regular drinks consumed in one sitting, at two or more events within one months time span (Acuff, Soltis, Dennhardt, Bosari, Martens, Murphy, 2017). Another repercussion from binge drinking is second-hand effects. Inevitably, those students that are partying and drinking need the support and guidance of their more academically minded friends. Following a night of drinking, perhaps the drinker needs a ride from a sober friend or perhaps there was drama centered around those that were drinking and need the comfort and encouragement from their sober counterparts. A negative experience with alcohol as a non-drinker defines second-hand effects (Cabalatungan, & McCarthy, 2015).

18. Suppose that the scores of architects on a particular creativity test are normally distributed. Using a normal curve table, what percentage of architects have Z scores:

standard deviation standardized value rescaling z-score normal model parameter statistic standard Normal model 68-95-99.7 Rule normal probability plot

The margin of error is 2%, “that is the amount of error that the CEO finds acceptable for him” (The Importance and Effect of Sample Size) (2016). If 90% of the people that were surveyed said yes, and 10% answer no, the CEO tolerance level for error might be able to be increased the it being 50/50. The confidence level that is trying to be reached by the CEO is 95.44. The confidence level is the doubt the CEO will tolerate. Let’s say the CEO has 30 yes or no questions on his survey. Having a confidence level of 95%,

The t-test is a parametric analysis technique used to determine significant differences between the scores obtained from two groups. The t-test uses the standard deviation to estimate the standard error of the sampling distribution and examines the differences between the means of the two groups. Since the t-test is considered fairly easy to calculate, researchers often use it in determining differences between two groups. When interpreting the results of t-tests, the larger the calculated t ratio, in absolute value, the greater the difference between the two groups. The significance of a t ratio can be determined by comparison with the critical values in a

This study was developed in order to discover what university students saw as binge drinking.

a) Does the range rule of thumb overestimate or underestimate the standard deviation for the number of people living in your home? Q17

In another study done by Stephen Porter and John Pryor (2007), they related the number of drinks per week to time management and grades by separating the groups into gender and school type. Women typically seemed to spend less time drinking, especially at all women’s schools or research universities, than men at any kind of university. For the students who did seem to engage in heavier drinking, the smaller amount

Although all types of drinking can have adverse effects, there are different levels of use that result in different effects. Moderate drinking is defined as drinking that generally does not cause problems in the drinker or society, typically one drink per day. This low level of alcohol consumption has been shown in studies to, reduce stress, decrease tension and anxiety, (NIAAA, 2000). Social drinking generally does not cause problems with the individual as long as the amount consumed does not increase over time, but this level of drinking has not been known to have any positive effects. Binge drinking is classified as having five or more drinks in one sitting. This is the level of use that college students engage in on the weekends. Some social effects that have been noted by students are the increased ability to "break the ice" in conversation, allowing people to have more fun, and facilitating sexual opportunities, (Statistics on Alcohol, 2000). However the Core Institute survey showed that of the students who had engaged in binge drinking at least