1. A group of 320 male students from the local high school has a mean mass of 70.41 kg. Records of similar students countrywide show a mean mass of 70.0 kg. A researcher wishes to determine whether the local students differ from the national group. (a) Describe the research problem (b) Write a null and alternate hypothesis to facilitate the investigation. (c) Suggest an appropriate statistical test. (d) Should the test be one-tailed or two-tailed? (e) Give reason(s) for your answer at (c).
2. An investigation to determine whether men are taller, on average, than women revealed the following results: - A group of 1164 men had a mean height of 174.46 cm with a variance (s) of 45.6522 cm, while a group of 1456 women had a mean height of 162.23 cm with a variance (s) of 43.6725 cm. A researcher wishes to use this data to determine whether men are significantly taller than women,' (a) Write appropriate hypotheses for the investigation. (b) Suggest an appropriate statistical test. (c) If the computed test statistic is 45.94 and the critical value at = 0.05 is 2.236. What statistical conclusion can be drawn? (d) Suggest an appropriate Confidence Interval and justify your choice (e) What can the researcher conclude from his/her investigation?
3. A survey was conducted in Black Bush Polder to study the adoption of improved farming practices by farmers. Farmers were classified according to their educational levels and categorized into early adopters, late adopters, and laggards. It was found that of the 130 farmers interviewed, 27 were early adopters and 63 were late adopters. In terms of educational levels, 21 farmers received secondary education, 57 finished primary schools, and the remainder did not complete primary education. The researcher wishes to find out if the educational level is related to the adoption rate. (a) Provide a suggestion regarding the research problem (b) Create a contingency to reflect the results of the survey. (c) Write appropriate hypotheses to facilitate the determination of a possible relationship. (d) In the analysis of the data, a computed value of 15.487 was obtained compared to the critical value of 7.175. Write a statistical conclusion in terms of the stated hypotheses. (e) Comment on the outcome of the study
4. The Ministry of Natural Resources wishes to determine the feasibility of establishing a Non-Timber Forest Products Industry in Region Two. A pre-feasibility study is therefore planned for purposes of data collection on the existing potential within the Region. (a) Provide an appropriate description of the research problem (b) Identify the target population(s) (c) Suggest five possible variables that may be targeted for data collection (d) Justify the choices made above (e) Suggest at least two bases for decision-making in this activity