Again, we assume that the (theoretical) population mean is 4, the sample mean is 5.0, and the sample standard deviation s is 1.936. Now, the standard error will be When N = 20, the critical value for a 5% significance test will be 2.09 (because the t-distribution curve is closer to the normal distribution). Why the t-distribution is a family of curves. 2  How critical t-values change as a function of the alternative hypothesis and the Type I error rate. 3  How to calculate t-values for a single sample t-test, an independent samples t-test, and a paired t-test.
The 805 Area Code (or Area Code 805) is located in the state of CA. Area Code 805 is one of the 269 3-digit telephone area codes in the USA.ry searching for any 805 Area Code phone number today, and discover what Spokeo can do for you. Top Cities. Oxnard, Arroyo Grande, Cambria, Simi Valley, Ventura, Thousand Oaks, Paso Robles, Newbury Park, San Luis Obispo and Guadalupe.
Area code 805 was put into service. Area code 805 was created from a split of area code 213. In 1999 area code 805 was split to form area code 661. Counties in California within area code 805 include: Monterey County, San Luis Obispo County, Santa Barbara County, and Ventura County.rea code 805 was created from a split of area code 213. In 1999 area code 805 was split to form area code 661. Counties in California within area code 805 include: Monterey County, San Luis Obispo County, Santa Barbara County, and Ventura County.