Micronesco Superstore has been selling 100 units of laundry detergent per day. After advertising laundry detergent in the newspaper sales were tracked for 14 days to determine if sales increased by a statistically significant amount. The data table reports the number of units sold per day. Micronesco wants to know if there has been a statistically significant increase in sales. Use 100 as the population mean μ. Run the following hypothesis test at an alpha α = 0.05.
n = __________ Calculate the sample size n.
x = __________ Calculate the sample mean x.
__________ Is the sample mean mathematically larger than the population mean of 100 units?
sx = __________ Calculate the sample standard deviation sx.
SE = __________ Calculate the standard error SE.
__________ Is the sample mean x different than 100?
Write out the null hypothesis that the population mean μ is 100 units:
H0:
Write out the alternate hypothesis that the population mean μ is NOT 100 units:
H1:
Run a hypothesis test at a risk of a type I error alpha α = 0.05
tc = ____________________ Calculate the value of tcritical
t = ____________________ Calculate the value of the t-statistic t
p-value = ____________________ Use =tdist(abs(t),n−1,2) to calculate the p-value.
____________________ Calculate the maximum confidence we can have that the sample mean does not come from a population with a mean value of 100 by calculating 1−p-value.
____________________ Is the sample mean x statistically significantly different from the population mean μ of 100 units?
_____________________ At an alpha α of 5%, would you fail to reject|or|reject the null hypothesis?
__________ Did the number of units of detergent sold change by a statistically significant amount?