Exam 2: The Spine of Statistics

Your business studies lecturer has set you the following hypothesis to test, 'there will be no association between consumer socioeconomic status and level of private health insurance'. What type of hypothesis is this?

A business analyst in a software design company reviewed a series of national surveys of user satisfaction (rated on a ten-point satisfaction scale) with a new gaming interface the company had recently launched. She found that the survey mean was 8. However, her standard error was high (89.5), how should she interpret her results?

You work in a data analyst unit for a large fast food restaurant chain, planning a customer survey and a colleague informs you that a 95% confidence interval has a 95% probability of containing a population parameter. Because of this, she insists that a survey distributed at one restaurant will provide significant results. Do you agree with her?

A financial analyst needed to calculate the mean income generated by the six most successful salespeople in her business over one month. The income figures were £1950, £3500, £4232, £4376, £2999 and £2165. What was the mean income generated?

A soft drinks company developed a new fizzy drink ('Delicious Fizz'). A researcher conducted a series of 'blind tasting' trials to measure consumer response to the new drink; this involved consumers drinking 'Delicious Fizz' and a rival fizzy drink ('Rival Fizz') and then rating the products on a ten-point taste scale. The results for consumption of 'Rival Fizz' and taste was p = 0.02, while the results for consumption of 'Delicious Fizz' and taste was p = 0.015. How should the researcher interpret her findings?

What is the power of a statistical test?

What does NHST stand for?

What do we call the situation where we believe there is a genuine effect in our population when in fact there is not?

Why are large samples desirable in statistical models?

What is the standard error?

A HR manager conducted a review of overtime worked by employees. Her sample size was 60 employees and there was a mean of 90 hours worked overtime per month. Her confidence interval was 95%. What would be the upper boundary confidence interval for this study?

In hypothesis testing, which hypothesis do we test?

A member of your market research team conducted tests of a new television advert with twenty different groups of consumers, in which they rated their satisfaction (on a ten point scale) with the advert and likelihood of purchasing the advertised product (on a five point scale). He is worried about the familywise error rate across the tests, what advice would you give him.

What is the SPINE of statistics?

What does it mean to label a statistical model a good fit?

You are the newly appointed business analyst for a large national bank (250000 customers). At a team meeting, your boss presents the results of a survey of customers regarding their opinion (measured on a ten point scale) of a new financial product. The survey sample (of 500 customers) showed a significant (p = 0.23) level of satisfaction with the new financial product. How should you interpret this result for your boss?