# probability distribution help

• Mar 25th 2014, 02:16 PM
John108
probability distribution help
 Category: Tenure by household size (owner occupied plus renter occupied) Number of household members for state Number of households in state with corresponding number of household members Relative Frequency 1-person household 732,263 28.7% μ 363867.8571 2-person household 813,166 31.9% Median 353,676 3-person household 417,216 16.4% Mode None 4-person household 353,676 13.9% standard deviation 291795.8781 5-person household 150,842 5.9% 6-person household 51,409 2.0% 7-or-more-person household 28,503 1.1% Total 2,547,075 Category Total Housing Units Number of households in state with corresponding # of rooms Relative Frequency 1 room 66,378 2.4% μ 311,578 2 rooms 80,730 2.9% Median 323,335 3 rooms 276,537 9.9% Mode None 4 rooms 436,370 15.6% standard deviation 161920 5 rooms 512,146 18.3% 6 rooms 500,359 17.8% 7 rooms 345,510 12.3% 8 rooms 262,841 9.4% 9 rooms or more 323,335 11.5% Total 2,804,206

I'm not sure if i did the relative frequency,mean,median,mode,standard deviation can someone take a look and im not sure about unusual values? Also what type of graph would be apporiate for this data a histogram? help would be very much appreciated!
(Nod)
• Mar 25th 2014, 02:52 PM
Shakarri
Re: probability distribution help
You are doing your calculations with the wrong figures. The category is what you want to find the mean of. For your first set of data where the categories are 1,2,3... 7 and the frequency of the ith category is fi the mean is

$\mu =\sum_{i=1}^7 i \times f_i$

The median is the value of i where 50% of the samples are less than or equal to i.

The mode is the value of i which is most common.

The variance can be calculated as

$\sum_{i=1}^7 f_i (\mu - i)^2$
• Mar 25th 2014, 03:30 PM
John108
Re: probability distribution help
i thought you had to use households category then divide by how many rooms