9 Testing of Hypothesis

9.1 Z test:

  1. A sample of 900 leaves has got a mean weight of 3.4 gm. Test whether the sample is taken from a large population of leaves with mean 3.25 gm and standard deviation 2.61 gm

  2. For a particular variety of wheat, it was estimated that 5 % of the plants were attacked by a certain disease. A sample of 600 plants of the same variety was observed and found that 50 plants were infected with that disease. Test whether the sample results are in conformity with the population.

  3. In a survey on paddy farmers in 2 Panchayat, it was observed that 100 out of 350 farmers were adopted New technologies for production in the 1st Panchayat and 250 out of 600 farmers were adopted new technologies in the 2nd pan. Test the prop of paddy farmers in 2 Panchayat with respect to the adaptaion of technologies?

  4. A breeder claims that the number of filled grains per panicle is more in a new variety of paddy ACM5 compared to that of an old variety ADT 36. To verify his claim a random sample of 50 plants of ACM 5 and 60 plants of ADT36 were selected from the experimental field. The following results were obtained. Test whether the claim of breeder is correct?

\(\overline{{ \ x}_{1}}\) = 139.4 \(\overline{x_{2}}\) = 112.9 S1= 26.86 S2 = 20.11

  1. The correlation between yield and number of panicles based on a sample of 7 plants of paddy was found to be 0.86. Test whether the correlation of the population can be equal to 0.9?

9.1.1 t and F test:

  1. The height of plants in a particular field is assumed to follow the normal distribution. A random sample of 10 plants selected. The height in cm. was recorded as 143, 126, 137, 109, 137, 120, 114, 120,126, and 131. Test whether the mean of the population is 120cm

  2. The effectiveness of two sources of nitrogen namely ammonium chloride and urea were tested by an experiment on rice. The grain yield from two samples under the two sources is as follows.

Ammo. Chloride: 13.4, 10.9, 11.2, 11.8, 14.0, 15.3, 14.2, 12.6, 17.0, 16.2, 16.5, 15.7

Urea: 12.0, 11.7, 10.7, 11.2, 14.8, 14.4, 13.9, 13.7, 16.9, 16.0, 15.6, 16.0

Assess which source of nitrogen is better for paddy.

  1. The data related to two random samples from two populations are given below. Test the significance between two population variances

Sample 1: 20,16,26,27,23,22,18,24,25,14

Sample 2: 27,33,42,35,32,34,38,28,41,43,30,37

  1. The following are marks obtained to students in two different subjects. Test whether there is any difference between marks of two subjects

Subject A:16,10,28,26,15,12,18

Subject B:30,18,35,51,40,60,17,55