Reference no: EM132851982
Case 1: Ratings of speaker systems
Consumer Reports posts reviews and ratings of a variety of products on its website. The following is a sample of 20 speaker systems and their ratings. The ratings are on a scale of 1 to 5, with 5 being best.
Speaker rating Speaker Rating
Infinity Kappa 6.1 4 ACI Sapphire III 4.67
Allison One 4.12 Bose 501 Series 2.14
Cambridge Ensemble II 3.82 DCM KX-212 4.09
Dynaudio Contour 1.3 4 Eosone RSF1000 4.17
Hsu Rsch. HRSW12v 4.56 Joseph Audio RM7si 4.88
Legacy Audio Focus 4.32 Martin Logan Aerius 4.26
Mission 731i 4.33 Omni Audio SA 12.3 2.32
PSB 400i 4.50 Polk Audio RT12 4.50
Snell Acoustics D IV 4.64 Sunfire True Subwoofer 4.17
Thiel CS1.5 4.20 Yamaha NS- A636 2.17
Required task to be solved:
1. How to compute the mean and median?
2. How to compute the first and third quartiles?
3. How to compute the standard deviation?
4. The skewness of this data is -1.67. Comment on the shape of the distribution?
5. What are the z-scores associated with Allison One and Omni Audio?
6. Do the data contain any outliers? Explain please