Two apparent experimental methods of increasing F are increasing the sample size and reducing the error variance by tight experimental controls.
tˈuː ɐpˈæɹənt ɛkspˌɛɹɪmˈɛntəl mˈɛθədz ʌv ɪŋkɹˈiːsɪŋ ˈɛf ɑːɹ ɪŋkɹˈiːsɪŋ ðə sˈæmpəl sˈaɪz ænd ɹᵻdˈuːsɪŋ ðɪ ˈɛɹɚ vˈɛɹiəns baɪ tˈaɪt ɛkspˌɛɹɪmˈɛntəl kəntɹˈoʊlz.