Question

The supermarket statistician realized that there was a considerable range in the spending power of its customers. Even though the overall spending seemed to have increased the high spenders still spent more than the low spenders and that the individual increases would show a smaller spread. In other words these two populations, ‘before’ and ‘after’, and not independent. Before the next advertising campaign at the supermarket, he took a random sample of 10 customers, Α to J , and collected their till slips. After the campaign, slips from the same 10 customers were collected and both sets of data recorded. Using the paired data, has there been any mean change at a 95% confidence level? A B C D E F G H I J Before 42.30 55.76 32.29 10.23 15.79 46.50 32.20 78.65 32.20 15.90 After 43.09 59.20 31.76 20.78 19.50 50.67 37.32 77.80 37.39 17.24

Answer 1

• ​This interim does exclude zero so the likelihood of "no change "has been dispensed with.
• Since the mean sum spent after the crusade is more noteworthy than that before it, there has been it,there has been a critical increment in spending .
• All in all: if the certainty interim incorporates zero ,i.e,it changes from negative to positive.
• At that point there is a probability that no change has occurred and the first circumstance has stayed unaltered .
• If as far as possible have a similar sign ,as above,then zero is avoided and some change more likely than not occurred.
• When deciphering this alter take a gander at the course of the change as this will rely upon your request of subtraction .
• in the above case clearly is certain so there has been an expansion in the normal spending.