Test statistics that follow a chi-squared distribution arise from an assumption of independent normally distributed data, which is valid in many cases due to the central limit theorem. A chi-squared test can be used to attempt rejection of the null hypothesis that the data are independent.
Voles, also known as mice, live in field, forest, and shrub habitats. Voles can cause extensive damage when they move into our turf and landscaped gardens in search of food and shelter. Voles do not hibernate and are active throughout the year. They can reproduce year round having many litters per year.
Four species of voles occur in Pennsylvania: the meadow vole, the pine vole, the red-backed vole, and the rock vole. The red-backed vole and rock vole are primarily restricted to mountainous areas, and it is the meadow vole and pine vole that are most often responsible in damage situations.oles eat a wide variety of plants, most frequently grasses and forbs. In late summer and fall, they store seeds, tubers, bulbs, and rhizomes. They eat bark at times, primarily in fall and winter, and will also eat grain crops, especially when their populations are high.